Representative democracies are supposed to be uniquely virtuous in that they ensure that public preferences drive public policy. Dynamic representation is the outcome of a recurring interaction between electorate and parties that can be observed at the macro level. Preferences can shape government policy via two possible mechanisms. 'Policy accomodation' suggests that governments respond directly to the electorate's preferences. 'Electoral turnover', on the other hand, assumes that preferences shape policy indirectly. Parties pursue their ideological goals, and public preferences respond 'thermostatically' by moving in the opposite direction to policy. This causes voters to switch votes and eventually leads to a turnover of power from one 'side' to 'the other'. In this paper, we estimate preferences for government activity ('the policy mood') in Spain between 1978 and 2017. We show that mood responds 'thermostatically' to policy. Variations in mood are associated with support for parties. Policy is driven by party control but is not thermostatically responsive to mood. It appears that in Spain - like Britain - dynamic representation can only be achieved by electoral turnover. We consider the implications of this for our understanding of how representation works.