How did the Solar System form? In this lecture I review the clues for the formation of the solar system in the present-day dynamics (orbital and rotation motions) and compositions of the planets and small bodies. I then describe the standard accretion model for solar system formation, whereby grains condense out of the primordial solar nebula, grains aggregate by collisions into planetesimals, then gravity begins to work and planetesimals grow into protoplanets. What kind of planet grows depends on where the protoplanets form within the primordial solar nebula: close to the Sun only rocky planets form, beyond the Frost Line ices and volatiles can condense out allowing the growth of the gas and ice giants. The whole process took about 100 million years, and we as we explore the solar system in subsequent lectures, we will look for traces of this process on the various worlds we visit. Recorded 2007 Nov 6 in 1000 McPherson Lab on the Columbus campus of The Ohio State University.