The Fermi Large Area Telescope (LAT) was successfully launched from Cape Canaveral on 11 June 2008. It is exploring the gamma ray sky in the energy range from 20 MeV to over 300 GeV with unprecedented sensitivity. One of the most exciting science questions that the Fermi LAT will address is the nature of dark matter. Several theoretical models have been proposed that predict the existence of Weakly Interacting Massive Particles (WIMPs) that are excellent dark matter candidates. The Fermi LAT investigates the existence of WIMPs primarily through their annihilation or decay into photons and into electrons. I will present the latest results on these searches.