When it comes to voting in parliament, party group unity is the rule rather than the exception in most (European) parliamentary democracies. But how do individual MPs come to their decision to vote... Show moreWhen it comes to voting in parliament, party group unity is the rule rather than the exception in most (European) parliamentary democracies. But how do individual MPs come to their decision to vote according to the party group line? This book introduces a theoretical model of MP decision making in which the main decision-making mechanisms, derived from the existing literature on the pathways to party group unity __ cue-taking, agreement, loyalty and obedience __, are placed in a particular sequential order. The three empirical studies in this book assess the relative role of each of the mechanisms, both independent and when possible as a part of the sequential model, in getting MPs to toe the party group line and contribute to party group unity, and explore whether this varies not only between parliaments (chapter 4), but also by levels of government (chapter 5), and through time (chapter 6). Show less