To assess integrated water policy performance, pollution abatement costs shall be weighted against overall policy implementation costs. The European Water Framework Directive (WFD) requires the design of cost-effective programs of measures (pollution abatement costs). Other policy implementation costs are difficult to identify and measure. We propose a transaction cost approach to balance the costs of programs of measures with overall costs or constraints related to the implementation process. We provide examples from France, Belgium and The Netherlands to illustrate transactions characteristics and transaction cost optimisation strategies. The factors affecting transactions constitute key elements for policy change.