A high purity measurement of $R_b$ at SLD

Precision measurement of Rb can provide important information about the Standard Model and beyond. SLD has developed a new method for measuring Rb with very high purity. This measurement has the lowest systematic error reported to date and future measurements using this method will likely have the lowest total uncertainty. This paper will be divided into the five sections: introduction, hardware, topological vertexing tag method, results and conclusions. The introduction will discuss the importance of Rb and the problems with other measurement techniques. The hardware section will give a brief description of the SLC/SLD system concentrating on its advantages over LEP. An outlook towards the future of SLD Rb measurements will be included in the conclusions.