  ESA's hard X-ray and soft gamma-ray observatory INTEGRAL is covering the 3
keV to 10 MeV energy band, with excellent sensitivity during long and
uninterrupted observations of a large field of view (~100 square degrees), with
ms time resolution and keV energy resolution. It links the energy band of
pointed soft X-ray missions such as XMM-Newton with that of high-energy
gamma-ray space missions such as Fermi and ground based TeV observatories. Key
results obtained so far include the first sky map in the light of the 511 keV
annihilation emission, the discovery of a new class of high mass X-ray binaries
and detection of polarization in cosmic high energy radiation. For the
foreseeable future, INTEGRAL will remain the only observatory allowing the
study of nucleosynthesis in our Galaxy, including the long overdue next nearby
supernova, through high-resolution gamma-ray line spectroscopy. Science results
to date and expected for the coming mission years span a wide range of
high-energy astrophysics, including studies of the distribution of positrons in
the Galaxy; reflection of gamma-rays off clouds in the interstellar medium near
the Galactic Centre; studies of black holes and neutron stars particularly in
high- mass systems; gamma-ray polarization measurements for X-ray binaries and
gamma-ray bursts, and sensitive detection capabilities for obscured active
galaxies with more than 1000 expected to be found until 2014. This paper
summarizes scientific highlights obtained since INTEGRAL's launch in 2002, and
outlines prospects for the INTEGRAL mission.
