 The ensuing discussion is organized as follows.  Section 2  describes a well-known version of an manipulability theory due to Menzies and Price (1993) which assigns a central role to the notion of agency or free action.  Section 3  describes reasons why the notion of a free action seems an inadequate basis for the formulation of a manipulability theory.  Section 4  introduces the notion of an intervention which allows for a more adequate statement of the manipulability approach to causation and which has figured prominently in recent discussion.  Section 5  considers Pearl’s “interventionist” formulation of a manipulability theory and an alternative to it, due to Woodward (2003).  Section 6  takes up the charge that manipulability theories are circular.  Section 7  explores how interventionist ideas can be used to explicate a variety of different causal concepts.  Section 8  returns to the relationship between interventions and human actions, while  §9  discusses the role of counterfactuals in interventionist theories. Sections  10,  11 and  12  consider the scope of manipulability accounts, while  §13  considers some objections to such accounts and  §14  some recent positive developments.