Investors do not lack for investment choices. Has the significant proliferation of choices helped improve investment outcomes or made the decision process just more challenging? Proliferation of choices is no more pronounced than among U.S. exchange-traded funds (“ETFs”). Since the launch of the first ETF in 1993, choices now exceed 2,500 funds. Investors have embraced them with combined ETF assets surpassing $6.1 trillion. In and of itself, the ETF vehicle is neither good nor bad. The investment focus of some ETFs may raise questions as could the manner in which investors deploy them in portfolios. A review of ETF dynamics can provide perspective for investing yet ahead.