Voluntary organisations should become more professional and shake off their "amateurish" image, a top expert has warned.

The new chairman of the Association of Chief Executives of Voluntary Organisations (ACEVO) said that "for too long, the sector has been hampered by its woolly, amateurish image".

John Low added: "Charity is no longer something that is done by the wealthy, in their spare time, to help the deprived. It is now a powerful, professional channel for harnessing collective action to achieve social change.

"My vision is of a modern, enterprising third sector. The sector must stop trading on its good intentions, and start trading on the results it achieves."

Low, chief executive of RNID, said charity bosses had a key role to play in transforming the sector.

"ACEVO has long been at the forefront of calls for a professional approach to leadership in the sector," he added.