As far as British television comedy is concerned, one of the few people genuinely entitled to quote the phrase 'Been there, done that, got the t-shirt' is Harold Snoad. Over a career in the industry spanning five decades, he filled every role from the gofer down on the ground floor to the grandee up in the gallery, and he did them all with distinction.

He came of age in the profession after the first wave of producer/directors, when most of the medium had already been mastered, but he proved himself so assured an operator in this environment that the BBC ended up picking him to train the next generation. Overseeing some of the Corporation's most popular sitcoms of the Seventies and Eighties, culminating in the internationally applauded Keeping Up Appearances, Harold Snoad came to epitomise the high standards of quiet professionalism that British television, at its best, now expects.

He joined the BBC in 1957, just before turning twenty-two, following a period of National Service and a spell spent acting in the theatre. Starting in television right at the bottom, doing the most menial tasks (everything from making tea at rehearsals to making sure the actors arrived on time for each recording), he flitted in and out of all kinds of productions, from the crime drama Dixon Of Dock Green to the sitcom Hancock's Half Hour, soaking up information and insights like a sponge.

His first stroke of good fortune came after three years of being a dutiful dogsbody, when he found himself in contact with a young producer/director named David Croft. Taken from the commercial company Tyne Tees by the BBC's then-Head of Light Entertainment Eric Maschwitz, Croft was regarded as one of the Corporation's bright young things, and was being fast-tracked on to a career shaping a succession of very popular comedy shows, starting with the student sitcom Eggheads and The Benny Hill Show (both screened in 1961).

Seeing how eager and energetic Snoad was in and around the office and the studio during these and other productions, Croft (who was almost thirteen years his senior) promptly appointed him his regular assistant. From this point on, Snoad, hovering closely over the shoulder of his new mentor, not only got to witness at first hand the rapid rise of one of the decade's busiest producer/directors, but also picked up every technique and trick Croft was using as he protected his autonomy and extended his power.

Aside, for example, from his careful preparation, his mastery of his cameras and crew and his far-sighted cultivation of a community of character actors who would help stamp his signature on one sitcom after another, Croft was also exceptionally crafty in the ways that he thwarted outside interference. If, say, a memo arrived from on high requesting to see some script or production plan, and Croft suspected it might prompt some doubts and delays, he would instruct Snoad to temporarily 'lose' the relevant papers, or else wrap them up and encase them, Russian doll-like, inside so many envelopes and jiffy bags (each one securely stapled and sealed) that the nosy executive usually ended up too frustrated or bored to bother pursuing the matter. Snoad, as the willing apprentice, learnt each one of these lessons - both conventional and decidedly quirky - with relish.

He was, initially, obliged to continue doing plenty of the dirty work of the production process, which included such tasks as dragging drunken performers from their dressing room and (after Croft had barked over the intercom: 'Get the bastard on - now!') literally kicking their backsides to propel them on to the stage (as happened when the American crooner Dick Haymes, having drained a bottle of vodka backstage, twice missed his cue during an 'as live' recording). Gradually, however, Croft started to groom his assistant as a producer/director in his own right, delegating more and more responsibility to him for the planning of projects, and giving him invaluable experience watching from the gallery as all of the scenes were shot.

Working together on such high-profile series as the long-running sitcom Hugh And I (1962-67) and the sketch-based The Dick Emery Show (which, for them, lasted from 1963 to 1964), Croft would sometimes let Snoad do some unofficial direction, especially during location filming, and in February 1968 handed him his first formal credit as director for an episode (Checkpoint Charlies) of the Hugh And I sequel, Hugh And I Spy. He also pulled some strings the following year to secure Snoad his debut as a series director for the Derek Nimmo sitcom Oh Brother!.

The two men would work together even more closely later that year once Croft started collaborating with Jimmy Perry on Dad's Army. Now not only producer/director but also co-writer of the programme, Croft needed to husband his time and energy more carefully than ever, so he was grateful to Snoad for assuming some of the more onerous of his many official chores - and Snoad, in turn, took this chance to demonstrate the range of skills that he had acquired.

Location work, in particular, was something on which Snoad now made his mark. Charged with the task of finding somewhere in southern England that could pass, regardless of the time of year, for Walmington-on-Sea and its surrounding countryside, Snoad eventually chose the cosy Norfolk town of Thetford - mainly for its pleasantly preserved areas (such as Nether Row) which could be made to seem so evocative of wartime England, as well as for the vast pine forest by its side - and also secured access from the Ministry of Defence to its nearby Stanford Practical Training Area, which was obviously ideal for setting, in private, all kinds of faux military exercises (and which also contained enough private roads, abandoned cottages, a river and even an old church to serve the needs of innumerable episodes).

Delighting Croft with the suitability of these places (as well as with the fact that there was such a pleasant and nicely-priced property for sale no more than a fifteen-minute drive away in Honington that the director snapped it swiftly up to serve as his family's new home), Snoad's efforts were greatly appreciated, and helped set him up as a key player in the sitcom's subsequent success. Indeed, starting with the second series early in 1969 (with the episode entitled Sgt. Wilson's Little Secret), Croft handed over a few of the directing duties to him (he would be in charge of five shows in total, as well as several of the location sequences), ensuring that he could begin to compile a portfolio that might help qualify him for future solo projects.

It did just that. In 1971, he was invited to make three shows with Eric Sykes; in 1972 he started directing pilot episodes for Comedy Playhouse, as well as producing Johnny Speight's Them and Ronnie Barker's His Lordship Entertains; and in 1973 he oversaw three instalments of another Ronnie Barker series, 7 Of 1, as well as the self-consciously saucy Leslie Phillips sitcom - much criticised by Mary Whitehouse - called Casanova '73. The following year, David Croft was pleased to be reunited with his old protégé when Snoad took over direction of the second series of Are You Being Served?.

Now very much established as a producer/director in his own right, Snoad went from strength to strength throughout the rest of the Seventies and beyond. Never unnerved by whatever challenges came his way, he was soon regarded as one of the safest pair of hands in the business.

He would forge a particularly strong and productive relationship with Dick Emery. It helped that, as Croft's assistant, he had worked with the comedian a decade before, but when, from late on in 1973, he became the comedian's regular producer/director, the two men (much to the relief of some anxious executives) struck up a rapport more or less immediately.

Emery, a notoriously neurotic performer whose career - although eminently successful - had been dogged by self-doubt, was known to have driven some directors to distraction with his chronic insecurity ('We would set the show on Monday,' one of them would recall with a pained expression. 'By Tuesday afternoon Dick had lost confidence in the sketches. By Wednesday he had metaphorically folded his arms and said, "Make me funny - I dare you"'). Snoad, however, seemed to know instinctively how to put the performer at his ease, and for the next eight years he became Emery's most-trusted colleague in comedy.

His success with The Dick Emery Show was one of Snoad's greatest achievements. It highlighted all of his skills as a producer/director - his meticulous preparation, his energy and intelligence, his sound judgement of material and performances, his eye for the sharpest and most striking comic scenes, his shrewd management of his cast and crew - and, in particular, it demonstrated his discreet but determined drive to keep a show evolving.

There was never a danger of the series stagnating while Snoad was in charge. Without resorting to jarring gimmicks or sudden stylistic changes, he was able to stand back every now and again and assess what aspects of the show might soon need pruning and which ones might benefit from cultivating more assiduously. The result was that, via steady evolution rather than rapid revolution, The Dick Emery Show kept coming back each year looking broadly the same and yet slightly different, ensuring that, in contrast to so many sketch-based shows, it rarely risked seeming stale.

Snoad was also imaginative, and shrewd, enough to seize on happy accidents. He responded, for example, to his star's growing habit (particularly when acting alongside Roy Kinnear) of 'corpsing' during takes by turning these cock-ups into extra comic clips, which he collected together and added to episodes under the banner of The Comedy Of Errors. This not only added further to the programme's subtle innovations, increased the quotient of laughs and (to the delight of the accountants) cut down on wasted tape, but also helped relax Emery during filming, encouraging him to see his mistakes more as opportunities for healthy self-mockery rather than yet more moments for forehead-slapping frustration.

Snoad eventually made Emery so positive-minded (at least by his own frangible standards) that he felt ready, in 1982, to experiment with a more ambitiously dramatic format - a six-part comedy thriller, entitled Legacy Of Murder, in which he played a struggling private detective as well as multiple other minor characters. Snoad, believing that Emery was actually a finer actor than he was a comedian, and better when he was concentrating on trying to be true to a character rather than seeking out laughs, worked hard with him to maintain that focus, while surrounding him with a lavish production that involved no fewer than seventy locations, including scenes shot in France and Tunisia.

However, Harold Snoad always remained keen to return to the world of sitcoms, and had jumped at the chance, while still working with Emery, to take charge of a new romantic-comedy by the 'love and laughs' specialist Richard Waring called Rings On Their Fingers. Running from 1978 to 1980, and co-starring Diane Keen and Martin Jarvis as the newly-married couple, it was in many ways a safe and perhaps even slightly cynical piece of mainstream entertainment, but thanks to the charm of the two actors and the polished precision of Snoad's production (and buoyed early on by the temporary absence of much of an alternative thanks to an ITV strike), it proved very popular with audiences, attracting as many as twenty-one million viewers over the course of its three series.

Following Emery's death at the start of 1983, Snoad settled on specialising in sitcoms, becoming arguably second only to Sydney Lotterby in that genre as the BBC's most trusted producer of the time. George Layton's Don't Wait Up, starring Tony Britton and Nigel Havers, lasted for six series in seven years (from 1983 to 1990), while Esmonde and Larbey's Ever Decreasing Circles (which Snoad took over from Lotterby in 1986, mid-way through its five year run) was even more of a critical, as well as ratings, success.

It would be with Keeping Up Appearances, however, that Snoad ended up being most closely associated. Written by Roy Clarke, it did not matter that this class-based comedy tended towards the cosier end of the sitcom spectrum, and relied on the kind of predictable scenarios that seemed to have already been featured in countless earlier comedies; it still touched on some enduring social truths, and some vivid social types, and it struck a seemingly effortless chord in middle England that resonated strongly throughout its five year run (from 1990 to 1995).

It probably would not have lasted quite so long, however, if Snoad had not been strong enough to guide it through some testing times. In his 2009 memoir about working on the show (It's Bouquet - Not Bucket!), he would be quite candid about the challenges that he faced on a fairly regular basis involving both the actors and the script.

Snoad was shrewd enough to realise that Patricia Routledge was perfect for the central role of the ludicrously deluded Hyacinth Bucket, while Clive Swift was similarly suited to playing her long-suffering husband Richard, but he knew that, by picking them, he would be obliged to preside over a decidedly prickly pair of personalities.

Routledge was not the warmest (nor the most generous) of colleagues, whereas Swift, on occasion, could probably have won a gold medal had irascibility been an Olympic event, and so Snoad sometimes had to work somewhat harder than usual to maintain morale and keep certain egos in check and fully engaged.

Snoad also encountered problems with the show's creator Roy Clarke, whose attitude to writing the scripts was similar to that of blowing his nose: he did it whenever he needed to, but he was never keen on studying the results. Remaining up in his beloved Yorkshire while the team worked away down in London, he sometimes exasperated his producer/director not only by submitting - in Snoad's opinion - sub-standard and/or impractical material, but also (according to the producer) by having no interest in 'improving' it.

This meant that Snoad felt he had no other option but to move ahead and rewrite some of the scripts himself, which caused Clarke, when he sat down and watched certain episodes and witnessed scenes and dialogue that most definitely had not originated with him, to react with fury at such interference. The BBC, while supporting Snoad's actions, eventually brought in a script editor, Christopher Bond, in a bid to calm the conflict, but relations between the two men would remain, at best, frosty throughout the rest of the show's span on the screen.

It was a rare error of judgement by Snoad to completely bypass Clarke (who was never really as difficult as his dourness might have suggested) rather than at least inform him of what was being changed, but it appears that, in this particular instance, a personal preference was impinging on a professional process. Instead of pushing Clarke harder for rewrites, or, failing that, bringing in a proper script doctor, the producer was overly eager to take over that role for himself.

Snoad's growing sense of self-belief as a writer as well as a producer/director had actually been causing the odd ripple of resentment within the Corporation for some time before he started clashing with Clarke. Having adapted, in collaboration with his actor friend Michael Knowles, the Dad's Army scripts for radio back in the early 1970s, and then in 1981 (again with Knowles) created the peacetime 'sequel,' It Sticks Out Half A Mile (about Pike, Wilson and Hodges struggling to renovate a local pier situated just along the coast from Walmington in Frambourne-on-Sea), for BBC Radio 2, he remained keen to come up with another writing project.

In 1985, after a long internal campaign, he and Knowles finally managed to persuade the BBC to let them film a pilot for a proposed series called Walking The Planks. A loose reworking of It Sticks Out Half A Mile (set as before in the immediate post-war period, but this time in the fictional seaside town of Midbourne and without - at least in name - the old Dad's Army characters), it starred Richard Wilson as a pompous bank manager and Michael Elphick as his dreamer of a brother-in-law, and was shot on Shanklin pier. It promptly sank under the surface, with one critic complaining that the 'script was so poor and the characters so unlikely that the writers risk being asked to walk the plank themselves'.

Undeterred, Snoad and Knowles continued working on the idea until, in 1987, they had enough material for a whole series, which they renamed High & Dry. 'I had to offer it to the BBC first,' Snoad would tell a journalist at the time, 'but they thought that to write [as well as produce] a comedy series was not quite the thing.'

This was somewhat disingenuous, seeing as none other than Snoad's old mentor David Croft was still going strong as a hugely successful writer/producer/director, but, after the BBC did indeed pass on the project, it was picked up by Yorkshire Television. Set as before in Midbourne (it was now actually landlocked Leeds), it featured Richard Wilson (again) as the bank manager, Bernard Cribbins as his brother-in-law and Angus Barnett as his rather naïve young nephew.

The BBC had told Snoad that, as a member of staff, he could only provide the scripts to ITV by using a pseudonym, so they were credited to Michael Knowles and 'Alan Sherwood'. It made no difference to the fate of the series, which came and went without many seeming to notice.

It also failed to sour Snoad's relationship with the BBC. Although, reflecting on the lack of encouragement for his writing ambitions, he lamented the fact that 'everything is so departmentalised' at the Corporation, he stressed to the press that he still regarded himself as committed, at least to a certain extent, to working for it: 'It's a way of life at the BBC,' he said. 'I like it and I'm very happy. I would love to work in the theatre but not on a full-time basis. If I wanted to work for ITV it would mean leaving the BBC, which I would only consider if I was offered a reasonably long contract'.

The BBC, in turn, still clearly held Snoad in such high regard as a programme-maker that, in 1988, it chose him to write its in-house training manual on his specialist genre: Directing Situation Comedy. Delighted to be asked, he approached the project with all of the enthusiasm, and a little of the mischief, of Machiavelli planning to prep his prince, filling the text with all kinds of technical but pragmatic advice drawn from years of calling the shots in the studio.

He is, for example, keen to encourage a healthy degree of scepticism about the kind of routine excuses one is likely to encounter ('Some writers say their adrenaline only flows when they are working against the clock, which is really just another way of saying that the script is going to be late'), while detailing the various technical tricks, especially in terms of editing, that can cut out numerous problems and leave one with a leaner sequence of what he likes to call 'drama with laughs'. What he doesn't avoid acknowledging, however, is just how all-consuming the work of a producer/director actually is.

'I would finish,' he writes, 'by saying that if you are directing a weekly series, remember you will need to have a lot of stamina to fit all the necessary tasks into a seven-day period':

He then concludes by stressing: 'MAKING PEOPLE LAUGH CAN BE QUITE A TOUGH BUSINESS'.

It seems plausible to speculate that one of the reasons why the BBC chose Snoad to write this guidebook was the fact that, of all its current leading sitcom makers, he was arguably the one who was best placed to communicate the common craft without an overly distracting accent. That is not to imply, however, that his own programmes lacked any personality.

While Snoad may not have been one of those producer/directors widely-known for a distinctive stylistic signature, many of his sitcoms were notable, nonetheless, for the knowing manner whereby they embraced the nature of their constraints. All sitcoms, in essence, are claustrophilic affairs, forever slamming shut their windows and bolting their doors, but few tended to be as visually constricted as the Snoad sitcom.

Everything is uncomfortably contained and close together: the houses, the rooms, the chairs and beds. It is the same with the characters themselves: the camera is always creeping up close to them, capturing their discomfort, and everyone is hemmed-in and hunched-up.

Martin Bryce's box room in Ever Decreasing Circles is perhaps the quintessential Snoad sitcom environment: an already tiny space made to seem and feel even tinier thanks to all three of the visible walls being lined by shelves stacked with meticulously labelled and ordered files, books, cricket membership forms, cul-de-sac communiqués and sundry other stationery, and the central area swallowed up by a desk, a chair, a typewriter, a telephone, an anglepoise lamp, a stocky stapler and a small photocopier - and, of course, the pinched and hidebound figure of Martin himself: quite easily the most claustrophilic human being in the whole of Mole Valley, if not the world.

This was a cramped and cluttered enough context during Sydney Lotterby's time on the show, but Snoad made it even more of a comical cage for this most tightly-coiled of characters. Indeed, by the fourth and final series, even Martin's work space was starting to shrink when the newly-expanding personnel department at Mole Valley Valves necessitated swallowing up fifty per cent of his office. 'You see, a lot of people couldn't cope if they lost half their office space,' a dazed-looking Martin tells everyone down the pub. 'Mr Bevis knew I could. I've been singled out as the chap who could continue to function efficiently with half his usual space.'

Even Snoad's solitary venture into movie-making, with the Ray Cooney farce Not Now, Comrade (1976), seldom allowed the camera to stray outside the constraints of one room in an over-crowded country house. All farces feast on confusions in confined spaces, but Snoad squeezed his action into a place so poky that it barely seemed able to hold enough air to sustain the full complement of characters.

It was partly this quality that ensured that Keeping Up Appearances, long after the conflict with Clarke had (at least to some extent) dissipated, maintained its comic appeal right through to the end, with the physical world getting smaller as the fantasy world got bigger (when the sitcom wasn't turning the screw inside a room, it was packing people into crowded church halls, over-loaded cars or suffocatingly-stuffed mini-buses). Hyacinth, with her booming voice and bloated sense of importance, seemed to take up more and more of the screen as all the other characters, and especially her inexorably-atrophying husband, appeared to scuttle back and forth along the sides like frightened mice ('I do believe,' she complains at one of the many times when she and Richard find themselves blocking each other's way, 'that you're expanding deliberately!').

Even when, in the penultimate series, the Buckets get to buy a 'cosy' apartment in a country house, it is merely, as Richard observes witheringly, 'a small apartment, and when I say "small," I mean micro!' He ends up stooping around the sloped-ceilinged attic bedroom - 'I can't sleep! I feel boxed-in! This place is too small!' - while she shuts her eyes and stays snug in her snobbish fantasy - 'Richard, I would ask you please to remember that our apartment in this Grade II listed mansion is not "small" - it's "old world bijou"!'

When Keeping Up Appearances finally came to an end, Snoad retired from the BBC and started working as a freelance. He realised his long-standing ambition to return to the theatre, directing the Willis Hall/Keith Waterhouse comedy Say Who You Are at The Mill at Sonning, and also acted as a consultant to many up-and-coming producer/directors from the comfort of his cottage in Sunbury-On-Thames.

Further potential television projects, however, suffered from a change in priorities within the industry, and he became so frustrated by what he took to be many broadcasters' declining interest in commissioning mainstream sitcoms that he took to defending the genre in print. Writing in 1998, he argued for more respect for the kind of comedies at which he had excelled:

Situation comedy is not dead, it is just being systematically killed off by TV bigwigs who cannot seem to understand that, on the whole, they are not providing fans with what they want to see. [...] In this current passion to be innovative, it almost seems that it is now more important for something to be 'different' than funny. Any normal character that could be recognised by the viewer (half the success of sitcoms) is now regarded as a stereotype. I get the impression that those in charge give the go-ahead to projects that they personally like with insufficient thought as to how it will go down with the mainstream audience. Something really has got to be done to give the public what they want - real characters in a strong, realistic, and, on the whole, believable situation.

While the response, for some time after, was not as positive as he had wanted, the many and frequent repeats of some of his own sitcoms would ensure that neither the old art, nor the old attitude, was lost entirely. Anyone seeking guidance as to how to accentuate the humour hidden in the parochial peculiarities of modern life will always find much to inspire them in a Harold Snoad sitcom.

That is the kind of legacy that he always wanted to leave. 'I'm very happy doing comedy,' he once said. 'It may sound corny, but I like making people laugh.'