Member States may entrust management and labour at the appropriate level, including at undertaking or establishment level, with defining freely and at any time through negotiated agreement the practical arrangements for informing and consulting employees. These agreements, and agreements existing on the date laid down in Article 11, as well as any subsequent renewals of such agreements, may establish, while respecting the principles set out in Article 1 and subject to conditions and limitations laid down by the Member States, provisions which are different from those referred to in Article 4.