Avalanche photodiodes are key components for many applications (telecom, ranging, sensing, spectroscopy,...) because their internal gain improves the photoreceiver sensitivity considerably. Two III-V materials of interest have emerged: AlGaAs and AlInAs, lattice-matched to GaAs and InP, respectively, and both characterised by a wide bandgap. In recent years, a breakthrough in the impact ionisation characteristics was identified and the major importance of a thin avalanche multiplication layer was clearly demonstrated.MARISE ambition is aiming to develop innovative engineered APD components with thin avalanche layers to benefit from their promising characteristics likely to advance the present state of the art. MARISE objectives are to push the limits of the new APDs in two directions: speed and sensitivity.For 10Gb/s access and single photon detection, AlInAs/GaInAs will be developed exhibiting low dark current and high responsivity,The development of a very challenging evanescent waveguide APD structure in the same material system will allow for 40Gb/s operation with a record gain-bandwidth product of 200 GHz.AlGaAs will be combined with a GaInAsN absorber into an innovative, very low noise and potentially low cost GaAs-based APD, suitable for 1.3 µm telecom applications.In MARISE, the APDs characteristics will be thoroughly assessed, and their suitability will be investigated for the following large-scale applications:· 10Gb/s burst-mode photoreceivers for broadband access and local area networks,· Core networks receivers at 40Gb/s based on waveguide APDs,· Single photon detection for use in secure communications.For each application, the impact of improved APD performance will be demonstrated in terms of increased receiver sensitivity and bandwidth, extended network performance, power budget or splitting factor.