More than 2,000 marched in Geneva on Saturday demanding better working conditions.
The march was one of a series across the country.
Although it was aimed at helping all workers, it was mainly the construction sector which made up most of the protestors.
New talks are due as several existing agreements covering building work are set to expire.
Unions are calling for pension protection, better pay and bad weather allowances.
Overall, the march was described as good natured.
It brought the Mont-Blanc Bridge to a standstill in the middle of afternoon as people stopped to listen to speeches.
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