When policymakers, communities or advocates make decisions and take actions, they do so with the purpose of achieving some desired goal. But sometimes, unintended consequences occur. These are outcomes that are not the ones intended by the purposeful decision or action.Unintended consequences can be positive or negative, although the discussions often focus on the unexpected adverse impact that may result from well-intentioned policies or public actions.It is tempting to say that unintended consequences happen because we live in an uncertain and unpredictable world, and that there is not much we can do to prevent their occurrence or prepare for them. In fact, many unintended consequences are neither predetermined nor random. It is true that whether or not unintended consequences happen will be affected by many economic and social factors that Singapore is confronted with, but much will also depend on how we approach these factors and the potential consequences.This book, based on the proceedings at the Behavioural Sciences Institute Conference 2017, explores various issues about unintended consequences in Singapore. The book is organised into four parts. Part 1 provides an overview of issues involved in thinking about unintended consequences. Part 2 examines unintended consequences in the context of Singapore's goal to become a smart nation and compares the perspectives between public and private sector organisations on dealing with uncertainty. Part 3 analyses the relationships linking unintended consequences to healthcare outcomes and the management of race relations in Singapore. Part 4 addresses specific questions on unintended consequences in Singapore in terms of the nation's history, immigration, education, meritocracy, civil service culture and mindsets, and relationships between people and government.This book will provide the reader new perspectives and possibilities related to achieving intended societal goals and building a strong Singapore society.