No time should be wasted in tackling these challenges, the review says.
On long waits, it says everyone on a waiting list should be reassessed so that those most in need are prioritised for help. There should no longer be a first-come, first-served approach.
Some of those waiting may benefit from non-medical support, advice about sleeping better or getting more physical exercise, for example. That may even lead to some being removed from the waiting list.
There should also be better assessments before people are placed on waiting lists too. Not every problem needs a medical solution, the experts make clear.
Quality and consistency of autism and ADHD assessments must be improved, with the review highlighting concerns about those done by the private sector on behalf of the NHS. Half of ADHD and a third of autism assessments are done by non-NHS providers, such as charities and private firms.
But they are not subject to the same regulation as NHS providers – and this must change.
The experts also said it wanted to see a ban on direct-to-public advertising of assessments.
The review has said it wants to see action over the next 12 to 24 months. The government has promised to act – and is expected to set out more details in its forthcoming mental health strategy which is expected by the end of the year.