This paper attempts to provide additional light on the structure and dynamics of inequality of opportunity among Tunisian children during the period 2005-2010. The main steps involved in the analysis comprise: estimation of the Human Opportunity Index, assessment of the relative contributions of circumstances, and decomposition of variations in inequality of opportunity in the factors driving them across time and space. The results reveal reasonable and declining levels of inequality in access to some basic services at the national level, but increasing inequalities between regions with Inland area lagging the rest of the country. The number of siblings and parents' education, wealth and location of residence are key factors causing such disparities. Without more inclusive and pro-poor policy actions, there are few chances for children belonging to the less advantaged circumstance groups to spring out of the poverty lived by their parents.JEL Classification: D63, D31, O18, O55