This book comprehensively discusses the topics in Buddhism that are crucial for promoting lay people's welfare--from mundane bliss in this life, i.e., wealth and good interpersonal relationships, to prosperity in the future, i.e., a good rebirth and less time spent in Samsara. This book presents some moral guidelines and a spiritual training path designed for householders and lay Buddhists, helping them secure the welfare. The guidelines and the training path presented in the book are based on the Pali Nikāyas and the Chinese Āgamas in Early Buddhism and an influential Chinese Mahayana scripture--the Upāsakaśīla Sūtra