Scientific Requirements and Prospects.- Prospects in space-based gamma-ray astronomy.- Annihilation of positrons in the Galaxy.- Prospects and requirements for measurements of extragalactic ?-ray lines.- Non-thermal cosmic backgrounds and prospects for future high-energy observations of blazars.- Rolling down from the 30 keV peak: Modelling the hard X-ray and ?-ray backgrounds.- Focusing supernova gamma rays.- Nucleosynthesis in nova explosions: Prospects for its observation with focusing telescopes.- Puzzles and potential for gamma-ray line observations of solar flare ion acceleration.- Gamma-ray Optics.- The INTEGRAL — HESS/MAGIC connection: A new class of cosmic high energy accelerators from keV to TeV.- Replicated nickel optics for the hard-x-ray region.- Small d-spacing WC/SiC multilayers for future hard X-ray telescope designs.- Design aspects of grazing angle multilayer mirrors for soft ?-rays.- Progress toward light weight high angular resolution multilayer coated optics.- InFOC?S hard X-ray imaging telescope.- Development of the HEFT and NuSTAR focusing telescopes.- The SIMBOL-X hard X-ray mission.- Laue diffraction lenses for astrophysics: Theoretical concepts.- Laue diffraction lenses for astrophysics: From theory to experiments.- Mosaic and gradient SiGe single crystals for gamma ray Laue lenses.- Copper mosaic crystals for Laue lenses.- High diffraction efficiency, broadband, diffraction crystals for use in crystal diffraction lenses.- An “ESA-affordable” Laue-lens.- Optical properties of Laue lenses for hard X-rays (> 60 keV).- Development of a new photon diffraction imaging system for diagnostic nuclear medicine.- HAXTEL: A Laue lens telescope development project for a deep exploration of the hard X-ray sky (>60 keV).- CLAIRE: First light for a gamma-ray lens.- MAX, a Laue diffraction lens for nuclear astrophysics.- The gamma ray lens — an ESA technology reference study.- Gamma ray Fresnel lenses — why not?.- Development of ground-testable phase fresnel lenses in silicon.- Multiwavelength focusing with the Sun as gravitational lens.- Focal Plane Instrumentation.- A Si/CdTe Compton Camera for gamma-ray lens experiment.- New scintillators for focal plane detectors in gamma-ray missions.- A focal plane detector design for a wide-band Laue-lens telescope.- Polarisation measurements with a CdTe pixel array detector for Laue hard X-ray focusing telescopes.- Simulated performance of dedicated Ge-strip Compton telescopes as ?-lens focal plane instrumentation.- Monte Carlo study of detector concepts for the MAX Laue lens gamma-ray telescope.- Performance of the Nuclear Compton Telescope.- The Compton and pair creation telescope MEGA.- Ground Facilities and Flight Systems for Focusing Telescopes.- The MPE X-ray test facility PANTER: Calibration of hard X-ray (15–50 kev) optics.- The Ferrara hard X-ray facility for testing/calibrating hard X-ray focusing telescopes.- SIMBOL-X: An hard X-ray formation flying mission.- Distributed space segment for high energy astrophysics: Similarities and specificites.- The CLAIRE gondola: Testing the first gamma-ray lens on a stratospheric balloon.- Recent advances and low cost concept for the gamma-ray lens project MAX.- Small-sat platforms and formation flying: An opportunity for the gamma ray telescope MAX.- MAX: Formation flying for nuclear astrophysics.- Formation flying for a Fresnel lens observatory mission.