Estimation of survival is used in many medical studies that aimed to estimate the prognostic of patient, the impact of some variables on the disease under study. More generally, estimation of survival is a valuable indicator of progress in disease control. For chronic diseases, more especially for cancer, the creation of registries has permitted to increase the knowledge in the epidemiology of the diseases under study. Over the past decade, population-based cancer registry data have been used increasingly worldwide to evaluate and improve the quality of cancer care. In this context, analyses are generally performed using methods of estimation of excess mortality that aimed at estimating and modelling the excess mortality to which a studied group of patient’s cancer is subjected and at estimating their net survival (i.e. the survival corrected for all the other causes of death). In this context, the objective of the modelling is to estimate the impact of prognostic factors on the excess mortality risk and to assess the cure rate in different subgroups of patients. Estimation of the survival of cancer’s patients, obtained from population-based data collected by cancer registries, are analysed regularly and published by the different European countries. Comparisons between countries are justified only if the methods used for that have taken into account bias relative of observational studies and if they are the result of a thought and a strategy adopted by all the partners. The development and the homogenisation of such methodology are totally justified in this context. The overall aim of this project is to improve the current methods for estimating net survival and to broaden their field of application in order to obtain i) tools to model complex data, and ii) more accurate estimates that enable to have information on survival for a studied disease and on its public health impact. More precisely, there are three main research axes devoted to: (1) propose new methodological developments to answer questions that are the result of our works during our previous project (MESURE); (2) extend and assess new statistical methods; (3) transfer net survival methods used in cancer to some other specific applications. These themes correspond to some of the actual challenges in the estimation of net survival. Following our previous project, CENSUR project is more ambitious, considering the scope of the methods investigated and the new development that are envisaged. While the focus is on methodological aspects, the network implies also members that have skills in epidemiology and in population-based data analyzes with the objective to produce survival statistics useful in Public Health. This project will allow to reinforce a network including 5 French team, 3 European and 1 Canadian, having complementarities, internationally known, and having experience in the framework of excess mortality and the development of statistical methods. At the end of this project, in order to optimize the use of methods to estimate net survival, we will organize a course. Furthermore, free-licensed statistical programs derived from our work will be available for the scientific community. If the project goes on well, it will allow to propose an adapted methodology in order to obtain correct estimates of the excess mortality for a disease under study and to its determinants. This methodological approach is a preliminary condition for a rational management of disease, on its medical and socio-economic aspects, that will be obtained from registries data, clinical data, or enterprise data.