This study focused on the motivation of K-12 teachers to participate in district online professional development and to sustain the knowledge or skills learned. This study identified how teachers in a suburban school district, located in the Hudson Valley region of New York state, evaluated the online professional development they received and the extent to which their learning continued beyond the initial training. Through a phenomenological study, data indicated several factors motivated teachers to participate in online professional development; the primary motivator was the relevance of the topic. The online survey and interviews indicated teachers were interested and willing to participate in online professional development when they could choose the topic and the setting in which the learning takes place. An additional motivator was the benefit of collaboration and support provided by the facilitator, both during and after the training. Teachers shared their ability to make connections and to reflect on their own experiences increased when they had the opportunity to work collaboratively with the facilitator to develop and implement a lesson using the new knowledge or skill. Teachers who identified taking relevant district online professional development with collaborative facilitators also reported specific examples of how they implemented skills in their classrooms. Teachers described how the district online professional development helped to improve their students' learning. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]