For retirees who want added security that they will not outlive their savings, "immediate" annuities may be the way to go. Immediate annuities are life insurance products that provide retirees with guaranteed streams of income for the rest of their lives. Paul J. Coleman, manager of Investors MarketPlace at Park Bank of Milwaukee, says a growing number of retirees are seeking such guarantees. John M. Fenton, a principal with Tillinghast-Towers Perrin, predicts that interest in immediate annuities will only increase among retirees, as more rely less on Social Security and defined benefit pension plans and recognize the need to guarantee at least a portion of their savings.