Where Harlesden had been black, Oxford was white. I went from being the only white kid on the team to the only black kid on the team.

Are you black, brother? Growing up, I just was. My mum was white and my dad was brown. My mum's relatives lived here, and the old ones had German accents. My dad's relatives lived in Israel and mostly couldn't speak English. When we went there, they said things in a funny language and pinched our cheeks. They smelled of garlic. And they came, originally, from exotic-sounding places like Bukhara and Isfahan (in today's Uzbekistan and Iran respectively).

This was no big deal. My friends' families came from Jamaica and Guyana and India and Ireland and England and Wales and Spain and South Africa. I was vaguely aware that I was Jewish; but everyone was something. None of it seemed very serious.

Things started to change when I went to secondary school. My state primary had been mixed, multicultural, and multi-ability. My new school was private, posh, and predominantly Jewish. But these Jews weren't like my family. They were all white, and a lot of them were blond with blue eyes. Not only that, but they liked football, talked like cockneys, and lived in the suburbs. They went to synagogue - 'shul' - and hung around only with other Jews. Some of them called black people 'schwarzes' and brown people 'pakis' and they didn't know what to make of me, this olive-skinned Jew who didn't practise. One of them told me that because of my irreligiosity the Messiah would not be coming.

At about 14, I started playing basketball seriously. The Harlesden Cougars basketball club was 99% black. The other 1% was me. I wasn't black, and couldn't understand the patois into which the other guys sometimes lapsed. I was basically the white kid, or the whitest they had.

And then came university. Where Harlesden had been black, Oxford was white. I went from being the only white kid on the team to the only black kid on the team. The blackest they had, anyway. They even told me that I had natural athleticism but lacked control and shouldn't shoot the ball.

Away from the basketball court I had a few amusing incidents. One night, a very drunk, very blonde girl staggered into my room. 'I've never really met a coloured person before,' she confided in me. When I told her that we didn't say coloured, we said black, and in any case I was not black but Jewish, her reply was: 'I've never met one of those either'.

All this time, I scrawled sarcastic comments across any ethnic monitoring forms that came my way. Well, it's not nice when they don't have a box for you.

That became considerably harder after university, when I got a job running diversity policy for a big company. I learned about institutional racism and about monitoring and about glass ceilings and about how, at every imaginable stage in recruitment, promotion and termination, across all employment sectors, people with darker skin get treated worse than people with lighter skin with the same aptitudes and qualifications. And I understood that without hard data, you couldn't prove this was happening, and do anything about it. And that I ought to fill the form in. So I started to tick the box 'mixed race'.

As part of the job, I started to try and get more people from different ethnic backgrounds to apply to the company. I went out and started talking to groups of black people or Muslims or whatever. And they all thought I was one of them. The black people thought I was black - light-skinned, certainly, but black. Muslims assumed I was Muslim. Indians had me down as an Indian. Arabs thought I was an Arab. Greeks - well, check the surname: Mokades.

Sometimes my job took me to America. On one especially memorable trip I was picked up at the airport by a driver called Raul. Raul was overjoyed to see me. Instead of shaking my hand, he bumped my fist. As we walked through the car park he told me that he was a music producer, who drove cars on the side. He told me that reggaeton - a sort of fusion of dancehall, hip-hop and Latin American sounds - would be the next big thing. And then he looked me in the eye and asked: 'Are you black, brother?'

I told him no, not exactly, but it didn't matter. He'd made his mind up - I was a brother. So he was going to show me Harlem. And as we crossed 110th street, down went the windows, up went the music, and out came Raul's chat. 'Hey, shorty!'. 'Lookin' fine, sista'. 'Where you headin', girlfriend?' And so on. By the time the impromptu tour of Harlem was finished, Raul - who had confessed to me both that he had eight women on the go and that he was a member of the Nation of Islam - had decided I was not just a brother but a friend for life. 'Here's my number, man, put it in your cell phone and give me a call Saturday. I'm a go' hook you up with the finest ghetto sistas'.

So there you have it. I'm black and I'm brown and I'm a brother and I'm Indian and I'm Jewish and I'm Muslim. White people have told me I'm white, too: after all I went to Oxford and I talk properly, don't I? Wherever I go, I can fit in. So I'm everything. But I'm nothing. I fit in, but I'm never at home. I'm not part of a 'community'. I'm Jewish, but I don't practise, and I'm about as unlike your average north London Jew as it's possible to be.

So talk of 'people from ethnic minority communities' makes me feel a bit left out. I don't spring from a community. I'm not alone, either. Among my friends I count a woman who is half-Zimbabwean, half-English; another half-Filipino, half-German Brit; a guy who is half-Dutch, half-Nigerian; and so on. All of us have complex identities.

And it may be that in the future there will be more rather than fewer of us - the 2001 census suggested that mixed-race people had the youngest average age profile, and one in five of London's schoolchildren will soon be from mixed-race backgrounds. I know there can never be a box on those forms for every possible permutation of ethnic origin. But I also hope that as mixed-race people become more numerous and start to reach the higher echelons of British society, a more sophisticated understanding of ethnicity will evolve: one which allows people like me to be seen as a subtle shade of beige.

Raphael Mozades is managing director of Rare Recruitment, a recruitment agency for ethnic minority graduates. raph@rarerecruitment.co.uk

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