It is a fact that : « The public administrative structure of a modern society is changing constantly » (March and Olsen, 1983 : 281), but how does it change ? What do we mean by « change » in the structure of state organizations? Moreover, there are different types of changes in organizational structures. These are the central questions of our paper, which aims at: (1) Identifying and defining different types of changes in the structures of public organizations and (2) discussing the proposed categories on the basis of the "Democratic Reform of the State" implemented by President Rafael Correa in Ecuador between 2007 and 2017 (SENPLADES, 2009). To address the first objective, we will start from the categories proposed by the theory of population ecology (in order to identify different forms of birth, permanence and death of organizations (Rolland and Ronnes, 2011 : 400-402)) and then extend our classification to changes either at the horizontal level (in relation to the division of work and the distribution of tasks) or at the vertical or hierarchical level (Lagreid et al. 2003: 7-8). To apply our classification framework to an empirical case, we will analyze the changes made in the structures of the organizations of the Ecuadorian Executive branch during the period 2007-2017. These changes have been recorded in a database constructed from on the basis of presidential decrees. To analyze the changes we use descriptive statistics with R.
