The joint evolution of participation and compliance of farmers in a public VA, along with the evolution of the pollution stock is examined. Replica- tor dynamics, modeling participation and compliance, are combined with pollution stock dynamics. Fast-slow selection dynamics are used to capture the fact that distinct decisions to participate in and comply with the public VA evolve in di?erent time scales. Conditions for evolutionary equilibria and evolutionary stable strategies regarding participation and compliance are derived. Depending on the structure of the legislation and auditing probability, polymorphic equilibria indicating partial participation and par- tial compliance or monomorphic equilibria of full (or non) compliance could be the outcome of the evolutionary processes. Multiple equilibria and irre- versibilities are possible, while convergence to evolutionary equilibria could be monotonic or oscillating. Full participation and compliance can be at- tained if the regulator is pre-committed to certain legislation and inspection probabilities, or by appropriate choices of the legislatively set emission level and the non-compliance ?ne. Budget constraints associated with monitoring costs seem to produce polymorphic equilibria.