A system and method for ETF investing that provides a primary exchange traded fund (PETF) that comprises a plurality of shares, wherein the primary exchange traded fund comprises investments in a plurality of secondary exchange traded funds (SETF). The system and method enable intraday, or other periodic, trading of a variable number and type of ETFs through a single ETF, based on one or more categories and factors including, but not limited to, real-time NAVs.