A trustee of the Charity Finance Group has resigned, citing "management and governance shortcomings" and "defensive and negative responses" to any challenge he made to the organisation’s strategy or direction.
Uday Thakkar, managing director of the social change consultancy Red Ochre, said he was also frustrated by the way recent problems at the CFG were blamed on previous management and staff.
The CFG, which has more than 1,350 charity members, aims to champion best practice in financial management in the voluntary sector. It has 10 trustees.
"I truly felt that my contributions were not welcome," said Thakkar, who was a trustee for three years. "My continuing doubts in the chair, and, I accept, mutual distrust, compounded the issue.
"I accept that the other trustees are of a different mind, so I felt that I was a lone voice and it was best for me to step down."
Last year, two special advisers at the CFG, John Tate and Gill Gibb, resigned after an office move, a restructure and accounting revisions reduced its reserves from £251,000 to £61,500. Gibb had earlier been a trustee.
Thakkar said: "I had stayed on in the hope of being able to facilitate change internally. CFG is in a very lucky position in that membership fees roll in and the financial outlook does look healthy.
"It does to my mind cover up management and governance shortcomings. A new support team does now appear to be in place and may well shore up the management – again, having the income to do this is convenient."
A statement from Ian Theodoreson, chair of the CFG, said the board had every confidence in the executive, "which is achieving stunning results and which openly participates in a healthy exchange of views with board members.
"The organisation has over the last year grown its membership, had an extremely strong financial performance and been successful in recruiting an exciting and talented staff team. All of those factors point to an organisation that is thriving and growing in confidence.
"We believe our results will speak for themselves and look forward to publishing our report and accounts in September, once they have been audited."