When James Vernon moved, with his wife and two children, from the University of Manchester to the University of California, Berkeley, he thought he'd found paradise.
"The first six months felt like being on holiday," he says. "It was heaven. The food was terrific, the workload was relatively light. Life was sweet until we had to try and buy a house. Then it got more complicated."
The year was 2000. Already house prices in the San Francisco area were verging on the unattainable.
"Luckily the University of Manchester had agreed to keep my job open for me as senior lecturer in the history department, so I had some leverage when it came to asking Berkeley for more money," says Vernon, now a professor in history. "After prolonged negotiations the university gave me an extra housing allowance to last five years."
The next shock for Vernon was his new colleagues' powerful work ethic. He was used to his more laid-back English peers. "I found that in California you're seen as inadequate if you can accommodate someone for lunch with under a week's notice," he says.
The third shock was a powerful surge of homesickness, which has never quite gone away. "I miss my friends. And I miss my family. When my wife and I first came to California we aimed to give it five years. I've found that the pain of separation actually becomes harder. I don't think: 'Wow! I'm here. How cool and different it is.' I think: 'My God! I could be stuck here for ever!'"
These are challenges that face nearly all British academics considering work overseas. The first is landing the job that justifies leaving home, family and country. The second is ensuring that a new overseas lifestyle matches one's expectations. The third is working out if, when and how one returns, ideally several steps up the ladder or with a good pension.
It's a balance that Vernon has yet to achieve. "I don't want to die here," he says. "But the longer we are here the harder it is to go back to England. I'm financially better off if I stay.
"If I returned to the UK now I would get a smaller salary and lose a good deal of my pension. Whereas if I stay in the States there is a very good retirement scheme where I will have 80 per cent of my salary once I've served 30 years. Since I started work here when I was 35 years old, that would be possible."
Each year about 500 British academics take up academic posts overseas. Twenty-three per cent of them go to the US, 41 per cent to the Continent and 36 per cent to universities in the rest of the world, according to the latest data from the Higher Education Statistics Agency.
Many of those who leave return, but a large proportion does not. Before they know it they have married into the new culture, started families and even turned against their country of birth and its higher education system.
"When I left England I told my mother at the airport that I'd only be gone a year," says geographer Trevor Barnes. He did his undergraduate study at University College London in 1978 and his MA and PhD at the University of Minnesota before moving to Canada in 1983 when he accepted a position at the University of British Columbia in Vancouver. "But I met my American wife and got such excitement from my department, such energy and vitality, that I decided to stay on.
"Once I'd decided to stay, it became harder to get out. From one decision everything else unfurled ... it is a powerful force of trajectory. My father has now had a stroke. My brother is bearing the burden and I feel tremendous guilt that I can't be there," Barnes says.
A major setback has also stopped him from coming home - he has multiple sclerosis.
"I've been approached a few times by British universities, but since my diagnosis I have had doubts about returning. My worry is the medical system in Britain. I get expensive drugs for multiple sclerosis free in Canada. A friend of mine in Britain has MS, and she has had to fight to get the same drugs."
Clearly there are pitfalls to living abroad. But whatever the shortcomings of working in North America, it seems that the challenges and rewards are sufficient to overcome most thoughts of coming home.
"Moving to Canada has allowed me to reinvent myself," says Derek Gregory, who left a job as lecturer at the University of Cambridge in the early 1990s to move (like Barnes before him) to the University of British Columbia's geography department. "If I'd have stayed at Cambridge everything would have become predictable. My research wouldn't have developed in the way it has. I needed intellectual renewal.
"Looking back, I realise how parochial my ideas at Cambridge were. I was lecturing to a sea of white faces. The students here ask questions and challenge my assumptions in the lecture halls - and they don't always wait until question time. In Cambridge the students would also challenge me - but only in small groups, not in lectures. What they could bring to discussions was limited by their life experiences. Here in Canada I've been forced to re-examine my own assumptions."
Vernon had the same sense of being stifled by his department before moving to California. "I liked America - the questions students were asking were different. I didn't want to have the same conversations for the rest of my life."
Another upside to working in North America is that wages, while not necessarily higher, tend to go further.
"I teach two classes a semester," says geoscientist Jeremy Crampton, who left Britain after graduating from the University of Liverpool "during the height of Thatcherism". He left because he couldn't get funding for his PhD. He got a job as a teaching assistant at Penn State University in central Pennsylvania, got his PhD and watched his career thrive.
"More than two thirds of my time is spent researching. I earn $62,000 (?31,000), plus extras if I teach in the summer. And my standard of living is higher than it would be in Britain. I bought a house in 2001 - it has three bedrooms and two bathrooms and is 1,300sq ft in a nice little neighbourhood in Decatur, (near) Atlanta," says Crampton, who is at Georgia State University.
Over at the University of Southern Maine, Matthew Edney earns $100,000, but notes that he pays $40,000 in tax. "I am an endowed professor, which partly explains my higher than normal pay. My job is research heavy, which is what I want. I teach one class for one of the two semesters - and that's it."
His lifestyle is very comfortable by British standards: "My wife and I have a 1924 kit house supposedly designed by Frank Lloyd Wright in Michigan. I also have an apartment here in Maine. But our plan is to sell both and buy a five-bedroom house."
But much depends on where you are based.
"Vancouver is very expensive - the twelfth most expensive city in the world," says Barnes.
"An ordinary two-bedroom flat can cost upwards of C$650,000 (?323,000). I have a British academic friend who is coming out to work here, but he has only been able to make that move with the help of a Canadian government scheme that funds prestigious chairs in selected departments."
"I was actually worse off in California financially than I was in the UK," says Vernon, when asked about the downside to moving to the US. "At Manchester my salary at the time was ?32,000, but my mortgage was ?30,000. In the US my starting salary as an assistant professor was $70,000, or ?50,000 at the time, but my mortgage was $280,000. And I made the mistake of selling my house in Manchester."
Another downside can be the high teaching workload - a problem particularly prevalent at state universities and further education colleges. Moreover, the student admissions system is more open at many institutions than it is in UK, with the result that many students are not particularly committed to their studies.
"Some of the 18-year-olds can be a real pain to teach," says Edney. "They don't do the reading or preparation. And most are not as academically qualified as they should be."
Crampton agrees: "Here at Georgia State the big introduction classes are a weeding out process. The university takes these students because it wants their money, but some of them shouldn't be there. They are not ready."
Part of the problem in North America can be explained by the "student as consumer" culture, says Crampton. "If they get a B or a C they send it back for re-marking and say: 'Can I have a better grade?'"
Gregory concurs: "Academics teach from textbooks because that's what the students want. Even the best students have adopted the 'skim, memorise and repeat' mantra."
British academics may also miss the atmosphere of the staffroom back home.
"There was a communal atmosphere in my department at Bristol, a sense of a common culture," remembers Barnes. "Coffee and tea times were key events; they helped solidify the department. People talked and got together. The atmosphere was collegiate.
"That doesn't happen here in Canada. People do their own thing. Academics see work time as too valuable to waste on socialising. It's not that people are unfriendly. It's just that salaries are tied to how many papers and reports we've published."
Faceless bureaucracies can add to the sense of alienation. "I moved from a democratic institution to a non-democratic one," says Gregory. "In England my faculty was essentially self-governing. Here it is made clear that I am an employee. Decisions are made along the lines of how best to commodify knowledge. To add to this there is an audit culture where everything has to be documented. It is anonymous and faceless."
Edney says that had he known how bad it could be administratively in the US he might never have ended up working at a university there.
For British academics still keen to try their luck in North America, the opportunities are there, especially for younger researchers.
"My advice to anyone thinking of searching for work in the States is to go for the big schools, just because there is plenty of money there and fun stuff to do," says Edney.
"The best time to apply is after completion of a PhD - that's when you can break into the jobs market most easily. The downside is the visa requirements. You can get a temporary visa but a green card is a lot harder." He recommends ensuring that lawyers' fees are included in the pay package.
Gregory's advice to academics thinking of working in the US and Canada is to focus on money. "Pensions and benefits are much better in the UK than in the US. Life is less certain in the States: all pensions are market based, so if your pension fund collapses you do too. Also, if you buy a home, estate agents' fees are much higher than in the UK.
"On balance, I'm glad I made the move," says Gregory. "I've benefited personally and intellectually. I miss Europe and I miss my close friends, and I miss the fact that in England you can walk for five hours and find yourself in a landscape with different language and food. But I can do without the yobbishness you get in Britain. The students here are unfailingly courteous. The culture is one of appreciation rather than entitlement."
"I'd be giving up a lot of friends in the States if I came back. I'd need a promotion," says Crampton. "And ideally I'd want a top job in a 'reader' position (with a salary of ?55,000). I'd have to be reassured of that in order to get over the high cost of living. But if the job was right I'd come back, particularly since my mother is still alive.
"I'm more senior now and have good contacts with senior British academics," Crampton adds. "The more places you have taught, the better you are perceived."
He is not alone in this view. Eight out of ten academics who left Britain to work abroad thought that their career had "strongly improved", according to a report by research management consultancy William Solesbury Associates. And those academics who do return to work in the UK continue to benefit from their links to American institutions, often leading to formal associations such as visiting professorships.
Edney says he has no plans to come back to the UK. "I know how to function in the States. And I'm not too keen on the way that academia has changed in Britain with the end of tenure and the present system of evaluation. It seems to be a lot more bureaucratic.
"There is a language of pedagogy that I have noticed creeping in back in Britain. I have a friend who is a pro vice-chancellor and he has started talking about a 'teaching interface'. This suggests an attitude towards teaching and research that is ... er ... different."
For some, circumstances have conspired to make a return to Britain impossible. But "I still think of myself as an Englishman," says Barnes. "I really enjoyed living in England. I was part of a much larger network of friends and families."
He pauses. "I'm just glad I get to return often."