Formal party statutes are practically a sine qua non for modern political parties. Yet these statutes vary greatly in terms of length, specificity, and even in the topics they address. This paper investigates differences in the ways that parties self-constitute, and what these differences reveal about parties’ internal dynamics, and about the challenges they face. Previous research on party statutes gives hints about what some of these differences might be (cf. van Biezen 2002, Smith and Gauja 2010), but prior studies have focused on (at most) a few countries. This paper conducts a much broader comparison, using the statutes collected for the Political Party Database project to compare over 150 parties of diverse ages, ideologies and origins, located in countries with diverse regulatory environments and electoral institutions. The paper particularly considers differences in emphasis between the statutes of established parties and those which present themselves as organizational revolutionaries, asking how much latitude parties have shown in re-inventing party structures.