As a general rule, the negotiation of the first collective agreement lasts up to six months. Negotiations on renewal agreements will also take a few months, but the old agreement will remain in force during negotiations. Collective agreements are generally valid for two years, sometimes three and sometimes one. Before the contract expires, the union and employer will enter into negotiations for a renewal contract. Only one in three OECD workers has wages agreed upon through collective bargaining. The 36-member Organisation for Economic Co-operation and Development has become a strong supporter of collective bargaining to ensure that falling unemployment also leads to higher wages.  Collective agreements are used to supplement legislation or to negotiate contracts specific to a scope. The main principle is that collective agreements cannot contain terms that are less than the statutory requirements. Workers are not required to join a union in a given workplace. Nevertheless, most industries, with an average union training of 70%, are subject to a collective agreement. An agreement does not prohibit higher wages and better benefits, but sets a legal minimum, much like a minimum wage.
In addition, an agreement on national income policy is often, but not always, reached, bringing together all trade unions, employers` organisations and the Finnish government.  Collective agreements also include decisions on working time and overtime pay. Trade Union Pro`s collective agreements include, for example, agreements on shift work differences, travel allowances, sick pay, maternity leave benefits, leave pay and child care benefits. Disability both employers and employees, whether individually or represented by trade unions and employers` organizations, have the right to take action in labour courts to request all the clauses of collective labour regulatory agreements that they consider invalid (Article 43, Collective Work Act). While a collective agreement is in force, it can only be amended by a voluntary and reciprocal agreement. An amendment to the duration of the agreement must be approved by the Labour Council. The Act is now enshrined in the Trade Union and Labour Relations (Consolidation) Act 1992 p.179, which provides that collective agreements are definitively considered non-binding in the United Kingdom. This presumption can be rebutted if the agreement is written and includes an express provision that it should be legally enforceable.