This paper focuses on mobilizations concerning migrants, asylum seekers and refugees in Greece. It analyses pro-migrant and anti-migrant citizen mobilizations and initiatives of solidarity and hostility. After briefly outlining key elements of national context, it offers a description of the migration flow in the country during and after the so-called refugee crisis of 2015. Moreover, it gives an overview of the description of the political environment regarding migration issues, offering an analysis of pre-existing citizen initiatives supporting migrants/refugees or civil society organizations which posit themselves as anti-migrant and giving a description of citizen mobilizations which have emerged since 2015. The paper describes pro-migrant and anti-migrant citizen mobilizations, highlights how these mobilizations have evolved over the last three years (2015-2018) and what has triggered and influenced those social movements of solidarity and hostility via 38 semi-structured interviews with mobilized citizens. It provides insights into the possible impact of these mobilizations on the policy agenda, on the reception arrangements for refugees and migrants as well as how solidarity and hostility towards migrants is organized and structured in the Greek society.