c) To pronounce themselves on economic and social plans and monitor their implementation; d) To be represented on social concertation bodies, as laid down by law; e) To take part in corporate restructuring processes, especially with regard to training actions or when working conditions are altered. 3. Trade unions have the competence to exercise the right to enter into collective agreements, which shall be guaranteed as laid down by law. 4. The law shall lay down the rules governing the legitimacy to enter into collective labour agreements and the efficacy of the respective norms. Article 57 (Right to strike and prohibition of lock-outs) 1. The right to strike is guaranteed. 2. Workers have the competence to define the scope of the interests that are to be defended by a strike and the law may not limit that scope. 3. The law shall define the conditions under which services that are needed to ensure the safety and maintenance of equipment and facilities and minimum services that are indispensable to the fulfilment of essential social needs are provided during strikes. 4. Lock-outs are prohibited. TITLE III Economic, social and cultural rights and duties CHAPTER I Economic rights and duties Article 58 (Right to work) 1. Everyone has the right to work. 2. In order to ensure the right to work, the state is charged with promoting: a) The implementation of full-employment policies; b) Equal opportunities in the choice of profession or type of work, and the conditions needed to avoid the gender-based preclusion or limitation of access to any position, work or professional category; c) The cultural and technical training and occupational development of workers. Article 59