(Spirit Rock Meditation Center) This talks focuses on one of the three areas of practice discussed a week before, on developing samadhi (or concentration), the theme of Donald's four weeks of practice in March. We begin by more generally discussing the nature of samadhi, including short account of the etymology in Pali, and the Tibetan sense of samadhi as "staying," as developing in the nine stages of the "Elephant Path." We look at the place and importance of developing samadhi in our practice and its relationship to insight practice; developing samadhi is one of the eight factors of the Noble Eightfold Path and appears in many of the Buddha's core teachings. We discuss some ways to practice developing samadhi, and then focus especially on several challenges of such practice and how to work with such challenges. The talk is followed by discussion, including further exploration of the relationship of cultivating samadhi and insight practice, the nature of skillful effort, and the joy that can arise in the development of samadhi.