When Dan Berelowitz was appointed Tzedek director four years ago, he was the international development charity's first paid employee, despite Tzedek having been operational since 1990.
He leaves the charity with a staff of 10, ready to move into their own offices, having raised more than £700,000 over three years. Mr Berelowitz - also chair of the Jewish Social Action Forum - is quitting to develop his own charity. But he will still feel "a really close attachment. You can't work in the charity sector without absolutely believing in the cause."
A trip to India to see one of Tzedek's partner projects is among his fondest memories. "We have supported 1,400 women over 10 years with small loans to start businesses," he reported. "In one generation, you can see a huge improvement in standards of living.
"Micro-credit does not work for the very bottom two per cent of people. But these women who we had helped were putting aside a few pennies into a communal pot to help the very poorest pay for housing. We were developing civil society, creating a whole social infrastructure. It's not glamorous, it has taken 10 years, but the difference is amazing. I love nothing better than that."
Mr Berelowitz said that in the wake of the Live Aid concerts in 1985, "people thought: 'Why is the Jewish community not doing anything?' And that's how Tzedek started. When I joined it was still small, earning about £50-60,000, with very committed volunteer trustees. It was like a start-up, but with 20-30 passionate volunteers."
It had been "easy" to convince the community of the value in helping impoverished communities in Ghana and India, sending Jewish volunteers on gap years to the areas and organising education and twinning with Jewish schools. "We are going to schools talking about Maimonides's ladder of charity - Oxfam will not do that. And we are giving people the opportunity to have a Jewish experience in the developing world. That's really important, because these people are on gap years anyway. "
Although fundraising had become more difficult, Tzedek's income was rising year on year. In March, it will move out of JHub, the Pears Foundation's subsidised space for emerging Jewish charities and organisations. "They are ready for us to go. We are a success story of the Hub.
"I like starting new things. I like good ideas that take seed. I've taken Tzedek so far and someone else will take it to the next level."
He explains his new project, the International Centre for Social Franchising, as "just like commercial franchising. It means good, charitable ideas can be replicated by different individuals. Charities like Food Bank have done this already. Now they have around 140 locations across the UK."
A board is being assembled and Mr Berelowitz hopes to begin with consultancy work, having already won a contract with Big Society Capital. As a new father, "I would not have handed in my notice without a pretty solid framework and pledges of support".
He leaves Tzedek at the end of the month and the JSAF will hold elections in the spring for a replacement chair. Mr Berelowitz will become chair of JSAF's advisory board. New campaigns planned for JSAF include one to encourage community organisations to adopt the Living Wage campaign for their employees.