Overview of an extensive multi-wavelength study of GX 339−4 during the 2010 outburst

Context. The microquasar GX 339−4 experienced a new outburst in 2010: it was observed simultaneously at various wavelengths from radio up to soft γ-rays. We focus on observations that are quasi-simultaneous with those made with the INTEGRAL and RXTE satellites: these were collected in 2010 March–April during our INTEGRAL target of opportunity programme, and during some of the other INTEGRAL observing programmes with GX 339−4 in the field-of-view.