Limited access to healthcare for vulnerable immigrant children in Europe and North America is increasingly worrisome as immigration policies harden. This paper analyzes the gap between States' obligations under international human rights law and the disparate local implementations in diverse countries. Studies that are both multidisciplinary and incorporate micro and macro level indicators are needed to reveal discrepancies between entitlements and access. It is argued that the lack of available data on the magnitude of the problem and on its individual and public health consequences stems from the conflicting situation faced by health institutions required to simultaneously protect the best interest of each child and allocate limited resources. Collaboration in research is urgently needed to assist policy-makers and institutions make informed decisions.