EuNPC2015

One of the open challenges in subnuclear physics is to understand the non-perturbative regime of quantumchromodynamics, including the world of the nucleon and its excitations. One of the key issues here is to identify the relevant degrees-of-freedom and the effective forces between them. A necessary step towards this aim is undoubtedly a precise knowledge of the experimental spectrum and the properties of baryon resonances. Recently, photoproduction experiments have made large progress providing not only differential cross section measurements but also high quality single and double polarization observables. Without the measurement of such polarization observables an unambiguous partial wave analysis to finally extract the contributing resonances from the data is not possible. In the talk, among other results, results from the recent double polarization experiments at ELSA, JLab and MAMI will be discussed.