Employers who sponsor 401(k) plans report using a range of default investment types to automatically enrol employees in their plans based on each type's design and other attributes. Department of Labor (DOL) created a regulatory "safe harbor" in 2007 to limit plan sponsor liability for investing contributions on behalf of employees into default investments when employees do not otherwise make an election. In addition, DOL identified three default investments that, if selected by sponsors, would qualify a plan for safe harbor protection. This book examines which options plan sponsors selected as default investments and why; how plan sponsors monitor their default investment selections; and what challenges, if any, plan sponsors report facing when adopting a default investment for their plan. Furthermore, this book determines what is known about the effect of automatic enrolment policies among the nation's 401(k) plans, and the extent of and future prospect for such policies; and the potential benefits and limitations of automatic IRA proposals and state-assisted retirement savings proposals.