Teaching unions have given a cautious welcome to the Welsh Government's new school banding system, but warned that its success will depend on the amount of support given to schools.
Last week education minister Leighton Andrews outlined the progress of the initiative, which was revamped from a grading system to avoid accusations of a return to league tables.
National data will be used to group primary and secondary schools - but not special schools - into bands reflecting their outcomes and progress.
It will give the Government's new school standards unit a starting point for discussions with local authorities and regional consortia about priorities for support, and provide a basis for resources to be directed to where they are needed most, Mr Andrews said.
"Banding is not about labelling schools, naming and shaming or creating a divisive league table," Mr Andrews said. "It is about grouping our schools according to a range of factors to establish priorities for differentiated support and identifying those from whom the sector can learn."
Dr Philip Dixon, director of education union ATL Cymru, welcomed the proposals and the minister's assurances, but said: "The proof of the pudding will be in the extra support that schools will receive to improve their performance. The success or otherwise will be judged on that."
NAHT Cymru director Anna Brychan said: "There is now a climate of expectation in our schools that this process will provide a level of expert, accessible and specialist support that many find hard to find now, and that this will be available consistently and to an equally high standard across the country. We very much hope that this promise can be realised."
But Rex Phillips, Wales organiser of the NASUWT, said he still had concerns about the system becoming a league table.
"We will seek assurances that schools will not be stigmatised if they are placed in the bottom band," he said. "A school in the bottom band is not necessarily poor or failing; there may be a host of reasons why the school is there. It is down to the minister to reassure the teaching profession that we will not go back to league tables."
A model banding system for secondary schools is currently being tested and will be finalised in time for the new school year in September, and work has begun on the primary model.
Secondary schools will know which band they will be placed into early in the autumn term and the reasons behind it.
Their banding will be based on external exam results from 2010, and updated with the 2011 results as soon as possible.
Original hadline: Support is key to successful banding system, say unions