Falling numbers of teaching staff could lead to an acute shortage in the future, a leading teachers' association has warned.
The comments come on the day statistics were released showing the number of pupils is likely to drop in the coming years and that more teachers are approaching retirement age.
The Federal Statistics Office predicted on Thursday that pupil numbers in both primary and secondary schools would fall by between eight and ten per cent by 2015.
The reason for the drop in number for those in compulsory schooling was changes in demographics, said the office.
Nevertheless, moves to lower the school entry age to four years old – it is currently between six and seven years old – could lead to a slight rise statistically in the number of pupils (1.5-three per cent), it added.
Teaching staff at primary schools were getting older, noted the office. In 1998, 20 per cent of teachers were over 50 years old. By 2004 this had risen to 30 per cent and it is projected to climb to 33 per cent by 2015.
The number of primary teachers expected to retire by 2015 will increase by 40 per cent between now and 2015. The situation remains more stable in secondary schools.
Although the statistics office said that this was likely to have a limited impact on recruitment - two-thirds of teachers retire before the age of 55 - the Swiss Teachers' Association reacted with concern.
In a statement, the association said there could be a shortage of teachers in the mid-term, especially in the early years of secondary school, and for science and maths.
It called for the measures to be taken to improve the attractiveness of the profession, including a special contract that takes into account work time outside lessons.
Better working conditions and a reliable human resources policy could help encourage well qualified and motivated people into teaching, the association said.
The association also called for teachers to be given enough space to do their job without too many extra rules and regulations.
The debate over education policy has been raging in Switzerland in recent years. The cantons are responsible for schooling, which means there are currently 26 differing education systems in the country.
Earlier this year the Swiss people and cantons voted in favour of a constitutional amendment on education which obliged cantons to harmonise the main aspects of the education system.
Currently it is not always easy to transfer between different cantonal systems and the school day is not always compatible with the hours of working parents.
Cantonal education directors are addressing these and other shortcomings. Proposals include two years of nursery school and day schools. But the measures are not likely to come into force before 2009.
Pressure to change is also coming from international comparisons, such as the Pisa study, which show that Swiss pupils are falling behind in some subjects.
swissinfo with agencies
Switzerland's 26 cantons enjoy a large degree of autonomy in education matters. They and the local authorities largely provide the financing.
Earlier this year, voters said "yes" to a constitutional amendment on education, which obliges cantons to harmonise the main aspects of the system.
This includes improving co-ordination among the different school systems and giving the federal authorities a bigger say.
Other reforms, planned for 2009, include streamlining the length of compulsory schooling and the school starting age, as well as binding regulations on the teaching of foreign languages, and all-day schools.