The rigorous professionalism dates from her early life in India, a period captured in the 1965 Merchant Ivory film Shakespeare Wallah, in which she starred - the tale of a troupe of actors taking Shakespeare to forgotten areas of India, which was based on the experiences of Felicity Kendal's own family. The film is being re-released tomorrow to coincide with the 50th anniversary of India's independence.
Felicity Kendal's links with India can still be seen in her house. Outside it looks small and homey: a bike up against the steps, a pint of milk left out and a cat mewing. But inside, in a deceptively large room, the lush images are all of India - lots of embroidered cushions, brass monkeys on the mantelpiece, wood carvings and brass boxes. Even the white slats on the windows give an image of darkened rooms in the heat of the midday sun.
It was India in the dying days of the Raj where she spent her formative years and where her acting skills were learnt. "I always toured. My parents toured before I was born. I happened to be part of the luggage," she says. "All my formative years and all my memories of childhood, except for a few horrible cold ones here in poverty-stricken digs, I spent in India."
Her parents had first visited India when she was a baby but left when Gandhi was assassinated, as they feared it was not safe. They then spent five years touring England and Ireland but decided to return to India after performing for the Mountbattens, who promised them help.
But Kendal's life was far from that of spoiled memsahib - she travelled all the time, staying nowhere for longer than three months. "There was no base, no home. It was really a sort of gypsy existence. I think I had a very free childhood until I started growing up and then I was put to work. I liked the travelling. I didn't much like the work early on."
The work was performing and helping backstage in her parents' company, which toured India performing "Shakespeare, Shaw and Sheridan". The young Felicity attended about 13 schools in quick succession as the company moved on but at the age of 13 she stopped going to school altogether. "My parents had this attitude that working in Shakespeare was as good an education as you could get - whether they were justified I don't think so but they believed it - and as far as they were concerned it was a perfectly respectable education and if I wanted to do something else later I was a fool but I could."
The result was nine years' gruelling work. "I did all the young girls. I did all the page boys you could imagine and a lot of the young boys. I understudied and did stage management, props and costumes. I think it was probably like theatres were 100 years ago - you didn't learn a part, you grew up hearing it - and then one day someone was off and you did it. It wasn't all that intense working out of the motivations. That was not something there was any time to do."
She accepted this life, she says. "At one point I wanted to be more settled. I wished I had a house with a picket fence and a bedroom which was mine, not a hotel room or a carriage in a railway station, but that was fleeting."
In Shakespeare Wallah, the daughter Lizzie (Kendal's role) is befriended by a handsome Indian Sanju. As their flirtation progresses the reality of the players' future becomes more and more apparent - they no longer have any real place or function in the new independent India. It was "very much a family film on a shoestring budget", she says - the parts of the mother and father were taken by Felicity's parents, Sanju was played by her brother-in-law Shashi Kapoor and her sister also played a part.
"The film worked because it wasn't sweet and gooey-gooey, all these actors having a lovely time, they picked a very tough line on it." But her parents were not completely happy with the result. "My parents on the other hand spent 30 years in glory and happiness, very poverty-stricken sometimes, but they had lived a life which they felt was a celebration of what they set out to do, so in that area they disagreed with the message of the film, which I think was slightly shortsighted of them."
But Shakespeare Wallah provided an escape route for her. Ismail Merchant took her to the Berlin Film Festival and then got her a good agent in London: "As soon as the opportunity arose I went. Neither of my parents really wanted me to go. They wanted me to stay and work in the company. But it just seemed obvious to try and leave home."
In London she found her Indian training counted for little. "I found it very hard to get any work at all. In fact I couldn't get any and it seemed an absolute eternity before the film opened. I could get nowhere because all the doors were tightly shut. A 17-year-old who says that she has nine years' experience in theatre doesn't ring true, does it? Most people's advice was `you must go to drama school because that's the way it is' and I was absolutely adamant I would do no such thing. Having worked all my life, to pretend to these people I didn't know how to put on a wig or ask what footlights were! Oh, I was very arrogant. I probably still am."
But from the beginning she carried off classical roles, working with Peter Hall at the National and with John Gielgud. Although her real fame came from The Good Life, in which she played devoted wife Barbara for eight series, the majority of her life has been spent in theatre.
At present she is acting in the Peter Hall season at the Old Vic in which she plays the lead in Harley Granville Barker's Waste, in repertory with The Seagull, in which she plays Madame Arkadina.
"Someone once asked me do you always play comedy," she says. "Actually I've played very little comedy but because I'm known for comedy on television they think that's what I do. In reality I can't remember the last time I didn't cry in a play."
She says that she will not be watching Shakespeare Wallah again. "I saw it years ago but I don't generally watch myself. But it was a definite part of my life."
As a result she has always chosen work based in a company: "It has always been that I want to work with people, it's not so much the part but a combination of the people involved in that project. It's obviously an imprint from childhood, recreating the structure. It's a very secure environment if it's working; if it's not it's hell on earth"
`Shakespeare Wallah' along with `Autobiography of a Princess' and `Heat and Dust' opens tomorrow at the Curzon Mayfair and Cambridge Arts Centre, and at selected cinemas around the country from 5 September