Member States shall ensure that appropriate and effective checks and monitoring mechanisms provided in accordance with national law and practice are put in place and that the authorities designated under national law carry out effective and adequate inspections on their territory in order to control and monitor compliance with the provisions and rules laid down in Directive 96/71/EC, taking into account the relevant provisions of this Directive and thus guarantee their proper application and enforcement. Notwithstanding the possibility of conducting random checks, inspections shall be based primarily on a risk assessment by the competent authorities. The risk assessment may identify the sectors of activity in which the employment of workers posted for the provision of services is concentrated on their territory. When making such a risk assessment, the carrying out of large infrastructural projects, the existence of long chains of subcontractors, geographic proximity, the special problems and needs of specific sectors, the past record of infringement, as well as the vulnerability of certain groups of workers may in particular be taken into account.

Member States shall ensure that inspections and controls of compliance under this Article are not discriminatory and/or disproportionate, whilst taking into account the relevant provisions of this Directive.

If information is needed in the course of the inspections and in the light of Article 4, the host Member State and the Member State of establishment shall act in accordance with the rules on administrative cooperation. In particular, the competent authorities shall cooperate pursuant to the rules and principles laid down in Articles 6 and 7.

In Member States where, in accordance with national law and/or practice, the setting of the terms and conditions of employment of posted workers referred to in Article 3 of Directive 96/71/EC, and in particular the minimum rates of pay, including working time, is left to management and labour they may, at the appropriate level and subject to the conditions laid down by the Member States, also monitor the application of the relevant terms and conditions of employment of posted workers, provided that an adequate level of protection equivalent to that resulting from Directive 96/71/EC and this Directive is guaranteed.

Member States where labour inspectorates have no competence with respect to the control and monitoring of the working conditions and/or terms and conditions of employment of posted workers may, in accordance with national law and/or practice, establish, modify or maintain arrangements, procedures and mechanisms guaranteeing the respect of these terms and conditions of employment, provided that the arrangements offer the persons concerned an adequate degree of protection equivalent to that resulting from Directive 96/71/EC and this Directive.