NACVS is to introduce a kitemark for members to make them more attractive to funders.
Local Councils for Voluntary Service will self-assess their own performances, which will then be verified by external assessors who will determine whether a kitemark can be awarded.
"Unfortunately, membership of NACVS is not proof of quality," said Julie Hawkins, chief executive of Barnet Voluntary Service Council, who proposed the motion.
"The standard gives us and funders a clear view of what we are doing and how we can improve."
NACVS hopes to receive Home Office funding for the scheme. Members will be charged for the assessment and will be required to undergo reassessment every three years.