The project concerns the availability, adequacy and access to social protection of three selected vulnerable migrant categories, i.e.: (i) migrants exposed to climate or environmental change; (ii) migrants in the informal economy, with specific reference to migrants who move in an informal work capacity and migrant workers who become part of the informal economy in the country/area of destination; and (iii) high-skilled professionals, including business persons and investors, and intra-corporate transferees. The analysis considers the holistic migration experience of vulnerability. This includes a focus on both cross-cutting migration determinants and the extent of the migration cycle. The core determinants relate to the gender and disability dimensions, but also the broader family (including vulnerable children and young people) contexts, and the regularity/irregularity of mobility. The migration cycle refers to the stages of migration experience or journey of the different migrant categories. Closely related to the drivers of migration, this includes consideration of the social protection status of these migrant categories at different stages –in their country/area of origin prior to migration; during their journey/transition to the country/area of destination; in the country/area of destination; upon return to and in the country/area of origin; and in relation to remigration/repeated migration.