Two cytoskeletal systems, two motor proteins, and three processes contribute to posterior determination of Drosophila oocytes. Two kinesin-dependent processes, directed transport and streaming circulation, deliver osk/Staufen RNPs from the anterior side of the oocyte to the posterior pole at stage 9 and stage 10B, respectively. At the posterior cortex, MyoV-based anchorage on actin cortex anchors and accumulates osk/Staufen particles locally.