This paper provides a basic introduction to workflows for shale oil/gas exploration risk and resource assessments. It starts with definitions of conventional and unconventional petroleum systems and brief descriptions of several North American unconventional plays. The core of the paper is a short description of workflows based on industry-standard Petrel and PetroMod software tools which enable rapid, auditable and geology based assessments of petroleum resources. The main steps of the iterative Exploration Risk Assessment workflow and its extension to include Petroleum Resource Assessments are described. The successful utilization these workflows is illustrated using a 3D Petrole