There are (2) general approaches to investing; passively investing in index funds and ETF's that generally mirror security performance in each of several market sectors, or investing in funds and ETF's that are actively managed to exceed the performance of a particular sector. My bias is inclined toward passive management within the large;mid cap and small cap stock market sectors with a small allocation to experienced active managers in funds more actively managed.
In the fixed income asset classes I also favor a passive approach for allocations in corporate and treasury securities, with a small allocation in the corporate space where managers are seeking to outperform by identifying securities that are eleigible for an upgrade in rating.