RF energy transfer and harvesting has been intensively studied recently as a promising approach to significantly extend the lifetime of energy-constrained wireless networks. This technique has great potential to provide relatively stable and continuous RF energy to devices wirelessly; it thus opened a new research paradigm, termed WPC, which has presented many new research opportunities with wide applications. Among these, the design and analysis of cooperative schemes toward efficient WPC have attracted tremendous research interest nowadays. This article provides an overview of various cooperative strategies for WPC, with particular emphasis on relaying protocols for wireless-powered cooperative communications, cooperative spectrum sharing schemes for cognitive wireless-powered networks, and cooperative jamming strategies toward wireless-powered secure communications. We also identify several interesting research directions in this area before concluding this article.