Human rights present a discourse that imagines racism-classism being overcome, and humanitarianism attempts to assist, save lives and alleviate suffering within this discourse. However, the case of irregular migrants transiting Mexico and the shelters that provide them with humanitarian assistance and defend their human rights tell us a different story. Drawing on participant-observation and in-depth semi- and unstructured interviews during 2012, this study explores the constitution, politics and practices of humanitarianism in the Global South through the lens of ‘coloniality’. It describes the shelter’s tensions with liberal Eurocentric principles of freedom, security and peace that especially affect poor, criminalised noncitizens in movement. The principle of free movement is basically anathematic to liberal humanitarianism and its basis in a security paradigm. Liberal humanitarianism is infused with assumptions about these principles, and it is these very assumptions that hold the humanitarian project hostage. This study reveals how human rights defenders in shelters support free dignified transit, collaborating with the entry of actors with liberal humanitarian agendas to shelters and simultaneously contesting the security paradigm on which liberal humanitarianism is based and which conflicts with the principle of free movement. Humanitarianism as it exists in the Global South thus presents a way out of the shadows of the liberal humanitarian security conundrum concerning freedom of movement.