In this thesis we show a reflection theorem for K2. We compare the 3-rank of K2 of the ring of integers of ℚ(√-3D) to the 3-rank of K2 of the ring of integers of ℚ(√-3D) and find that they differ by at most 2. We also show by examples that the formula we obtain is optimal. Introductions to algebraic number theory and classical algebraic K-theory are provided. A proof by Washington of Scholz's Reflection Theorem is given, and we discuss in detail results from Moore, Keune and Tate that describe the structure of K2 of a ring of integers of a number field F.