32 Operational-level grievance mechanisms perform two key functions regarding the responsibility of business enterprises to respect human rights. • F irst, they support the identification of adverse human rights impacts as a part of an enterprise’s ongoing human rights due diligence. They do so by providing a channel for those directly impacted by the enterprise’s operations to raise concerns when they believe they are being or will be adversely impacted. By analysing trends and patterns in complaints, business enterprises can also identify systemic problems and adapt their practices accordingly; • S  econd, these mechanisms make it possible for grievances, once identified, to be addressed and for adverse impacts to be remediated early and directly by the business enterprise, thereby preventing harms from compounding and grievances from escalating. Such mechanisms need not require that a complaint or grievance amount to an alleged human rights abuse before it can be raised, but specifically aim to identify any legitimate concerns of those who may be adversely impacted. If those concerns are not identified and addressed, they may over time escalate into more major disputes and human rights abuses. Operational-level grievance mechanisms should reflect certain criteria to ensure their effectiveness in practice (Principle 31). These criteria can be met through many different forms of grievance mechanism according to the demands of scale, resource, sector, culture and other parameters. Operational-level grievance mechanisms can be important complements to wider stakeholder engagement and collective bargaining processes, but cannot substitute for either. They should not be used to undermine the role of legitimate trade unions in addressing labour-related disputes, nor to preclude access to judicial or other non-judicial grievance mechanisms. 30. Industry, multi-stakeholder and other collaborative initiatives that are based on respect for human rights-related standards should ensure that effective grievance mechanisms are available. Commentary Human rights-related standards are increasingly reflected in commitments undertaken by industry bodies, multi-stakeholder and other collaborative initiatives, through codes of conduct, performance standards, global