Mainstreaming climate adaptation requires the inclusion of climate adaptation in the policies of various policy domains such as water management and spatial planning. This paper investigates the organizational values present in several municipal policy departments in order to explore their willingness to act upon climate adaptation and the implications for mainstreaming. Q methodology, supplemented by interviews and focus groups, applied in three major Dutch municipalities – Amsterdam, The Hague and Rotterdam – reveals three value patterns: (1) start today; (2) not for us to lead; and (3) shared responsibility. These different value patterns indicate that there is a general agreement on the problem, impacts and solutions, but disagreement on the time frame for action and the allocation of resources. Although all three value patterns are present within departments in each municipality, different value patterns prevail in each municipality. Additionally, the analysis shows barriers as well as opportunities for mainstreaming. A lack of political commitment and leadership, and unsupportive organizational structures, create barriers. In spite of this, there is willingness to act and strategic framing is applied to gain acceptance for the mainstreaming of climate adaptation.