This paper discusses some advantages and disadvantages of the most common digital tools for evidence gathering, and it explores some of the legal and practical issues arising from their use, drawing from cases where competition authorities across the world dealt with the delicate phase of evidence gathering in cartel enforcement. It was prepared as background material for the session "Digital Evidence Gathering in Cartel Investigations" held at the 2020 virtual Latin American and Caribbean Competition Forum on 28-29 September 2020.