"In the atomic nucleus, the interplay between single-particle motion, collectivity and pairing is seen as a rich tapestry of coexisting nuclear shapes and exotic excitations. For verifying and more detailed understanding of the shape coexistence phenomenon it is important to measure transition probabilities between the coexisting nuclear states.In the endeavour to understand the nuclear structure and related interesting phenomena, in-beam gamma-ray and electron spectrometers have been important tools. However, a gamma-ray or an electron spectrometer alone can provide only partial information of nuclear de-excitation processes. Moreover, electron spectroscopy with radioactive ion beams (RIBS), with very few exceptions, has not been exploited at all.The research objectives of the present proposal are:1) Initiate an electron spectroscopy campaign by performing simultaneous in-beam conversion electron-gamma-ray spectroscopy in the Accelerator Laboratory of University of Jyväskylä (JYFL).2) Develop similar techniques for complementary experiments, for the first time, with RIBS at REX-ISOLDE (and for future HIE-ISOLDE).The scientific aim of the present proposal is to extend the studies of shape coexistence in exotic nuclei by employing novel methods of in-beam conversion electron spectroscopy to investigations of electric monopole transitions (E0) and other highly converted transitions. Such studies have been carried out for nuclei close to the stability line but so far only very few attempts have been made for exotic nuclei close to the drip lines, especially when employing RIBs.The proposed project will be carried out at JYFL and provides a step towards a professional researcher and enables to diversify the physics interests of the Fellow. He will manage a large international collaboration and have a key role in the JYFL-ISOLDE collaboration with a scope of obtaining a tenure track position at JYFL. Such researchers are also needed in future RIBs facilities."