Building and maintaining a successful paid-search program is a difficult challenge that requires balancing many parts. Once launched, paid-search campaigns require constant maintenance and testing to assure they are achieving their financial goals. There are many ways ways to improve paid-search performance, and tools like OptiMine have been developed to help paid-search marketers keep their programs running at their peak. Where OptiMine focuses on solving the complex pricing problem associated with keyword bidding, others provide solutions for managing landing pages and ad text, conversion tracking and so on. All are important, but bid optimization has an immediate and noticeable impact on performance. The science of bid optimization has evolved from the early days (rules) to include different methods of mathematical modeling of keyword data. Each is effective to a degree, but the differences in performance are stark. Visit this page for a explanation of the various methods (rules and models) and their pros and cons.