The document discusses how personal learning environments (PLEs) can help form professional learning networks (PLNs) and transition learners from managing their own learning to collaborating in professional communities. It describes how PLEs allow learners to organize resources and connect with others, laying the foundation for PLNs. Learners then expand their PLEs into PLNs and eventually professional learning networks (PfLNs) focused on their specific interests and fields. Social networks and start pages that facilitate mashing up information are presented as tools that support this process of developing independently managed learning into networked professional development and knowledge sharing.