This paper investigates the technical efficiency of Angola oil blocks over the period 2002–2007. A double bootstrap data envelopment analysis (DEA) model is adopted composed in the first stage of a DEA–variable returns to scale (VRS) model and then followed in the second stage by a bootstrapped truncated regression. Results showed that on average, the technical efficiency has fluctuated over the period of study, but deep and ultradeep oil blocks have generally maintained a consistent efficiency level. Policy implications are derived.