The advent of femtosecond lasers in the field of solid state physics has been at the origin of many discoveries. For instance, in the field of magnetism it was possible in the last decade to understand how femtosecond optical demagnetization can probe the exchange interaction in ferromagnetic metals. The core of the UltrAMOX proposal is to explore how optically generated ultrafast acoustic waves interact with the magnetization of a thin film, and vice versa, how femtosecond demagnetization can lead to longitudinal and shear acoustic waves excitation from the release of magnetostrictive stresses. The later relevant physical framework is known as direct magnetostriction, which is the property of ferromagnetic materials that causes them to change their shape or dimensions during the process of magnetization or demagnetization. The reverse phenomenon appears when an applied external stress modifies statically or dynamically the magnetization configuration of a ferromagnet. A number of novel interesting physical phenomena can be expected to arise when an ultrafast acoustic pulse, excited through absorption of a femtosecond laser pulse at a photoacoustic transducer, is injected through a ferromagnetic sample (for instance a thin ferromagnetic film or a nanostructured array of ferromagnets). Under some specific conditions that have to be clearly identified, this generic idea termed "acousto- spintronics" could allow for ultrafast magnetization manipulation. Reversely, ultrafast demagnetization of magnetostrictive ferromagnets from femtosecond laser pulses is expected to release ultrafast acoustic pulses that carry out crucial information on the onset of spin-lattice coupling. The UltrAMOX project is a three-year fundamental and experimental project in which we aim to address the phenomena of direct and inverse laser mediated ultrafast magnetostriction in ferromagnets relevant to spintronics. We propose to merge picosecond ultrasonics where femtosecond lasers are used to excite ultrafast acoustic pulses, with femtomagnetism and spintronics. The goals of UltrAMOX project are twofold and can be listed as following: 1) Direct ultrafast magnetostriction: Investigation of the generation of THz longitudinal and shear acoustic pulses through laser mediated release of magnetostrictive stresses in ferromagnetic compounds. 2) Inverse ultrafast magnetostriction: Investigation of ultrafast interaction of laser generated ultrasonic pulses with spins and magnons in hybrid metal/ferromagnet multilayer structures.