We have said this in the past and are repeating it again – systematic investment plans (SIP) are to mutual funds what Xerox was to photocopy. The upside of investing in mutual funds through SIPs are that you get to invest small sums at fixed frequencies for the long run, which helps you acquire fewer units when the NAV is high and more units when the NAV is less. Effectively, over a period of time, you will average out your investment cost.