Robert Brown, convener of the Scottish Parliament's education committee, pledged on Wednesday after the committee gave outline approval for the Additional Support for Learning Bill that its provisions would make a "significant difference" to the experience of children in school who require extra help.
The record of needs system was "horrendously complex" and had left many parents dissatisfied at local level.
Mr Brown, a Glasgow Liberal Democrat, refuted suggestions that the revised system would end up by being more adversarial and equally bureaucratic.
Ministers were also promising to inject more money into the system to allay local authority fears about the substantially increased costs involved.
"The emphasis is on providing the service in the schools and if that is done right, all the rest will fall away. You will always have people on the edges dissatisfied with any system but the numbers who bang their heads up against a brick wall of local authorities should be lessened if the principles of the Bill are taken on by the authorities," Mr Brown said.
Peter Peacock, the Education Minister, will announce changes to the Bill next week.