In their recent review article, Mangano and Será (Journal of Environmental Management, 188:195–202) collate and describe the evidence base relating to the impacts of marine drilling platforms in the Mediterranean. The authors claim to have undertaken a systematic map using the Guidelines for Systematic Review in Environmental Management produced by the Collaboration for Environmental Evidence (CEE) as a basis for their methods. Here, I highlight major problems with their methods and the reporting of their activities. I demonstrate that a higher level of rigour and transparency is necessary for a true systematic map. Whilst their work is not without merit and may prove useful for decision-makers, their review could have been conducted and reported to a greater level of reliability. I stress the importance of transparency, comprehensiveness, and repeatability in ensuring that reviews are reliable and fit-for-purpose. I highlight the pitfalls of the authors’ approach in terms of: question framing; searching for evidence; the definition of grey literature; key outputs from systematic maps; and the dangers of vote-counting.