My main research topic is magnetism and spintronics of low-dimensional structures, with a special focus on magnetization processes with and within domain walls. I am mostly concerned with fundamental processes. To best understand these I investigate model systems for a better knowledge and control. This lead me to develop an expertise at the frontier of several areas : experimental and theoretical micromagnetism ; surface and interface magnetism; epitaxial growth and chemical synthesis, particularly for self-organization. In recent years I have been focusing on domain walls in cylindrical nanowires, with prospects for a three-dimensional race-track memory as background.