Temporary teachers in continuous work for more than a year are in line to win permanent contracts - but with variable hours. They may not gain full-time jobs.
Local authorities have moved to clarify the position of temporary staff after The TES Scotland last week revealed that Glasgow had dropped its court appeal against a part-time teacher who claimed she merited a permanent contract after working in the same secondary on annual contracts since 1994.
The test case victory means that all Scottish authorities will be forced to review the employment of part-time temporary teachers. Many have stalled their staffing exercises until Glasgow reached a decision about its court challenge.
Christine Pollock, co-ordinator of the Association of Directors of Education in Scotland personnel network, said the judgment did not mean that staff would be upgraded to full-time posts.
Ms Pollock, depute director in North Lanarkshire, said: "My understanding of the judge's decision is that teachers would be given permanent employment with the local authority and not to a specific school or post."
She added: "The judgment did not entitle the individual to full-time work.
Most local authorities would appoint - based on satisfactory performance - to a permanent supply pool and issue variable hours contracts. Different authorities would have to do it slightly differently."
Ronnie O'Connor, education director in Glasgow, said it was not unusual to have part-time permanent employees who would work different hours, depending on the needs of schools.
"We are looking for some flexibility in the Glasgow context of falling rolls and the changing curriculum. We do not know what the curriculum is going to be like in five years," Mr O'Connor said.
In his judgment last February, Gordon Coutts, QC, said: "It can well be argued that by operating the present system of employing temporary teachers (Glasgow) are seeking to make economies to the disadvantage of persons who are in fact full-time employees who are called 'temporary' and lack security."
Anna McGuinness, a Cleveden Secondary classics teacher, had been working full-time and part-time for six years but never for less than 0.6 of a week.