We present results on locally strained GaMnAs structures which were deposited by low-temperature MBE on GaAs substrates, GaInAs buffer layers, or self-assembled InAs/GaAs islands. The strain within the GaMnAs is modified by elastic strain relaxation caused by nanopatterning or islanding. The influence of local strain engineering in such GaMnAs/GaInAs nanostructures on optical and magnetic properties is investigated by high-resolution X-ray diffraction, photoluminescence, and magnetometry measurements. (c) 2007 Elsevier B.V. All rights reserved.