White hat SEO specialists follow the guidelines laid out by the search engines. A white hat SEO will make improvements to your website to make it more relevant for the search phrases important to your business. White SEO specialists will take actions to increase your website’s link popularity within the guidelines outlined by the search engines. White hat SEO specialists will never make any change or provide any service that could potentially put your website and domain name at risk of receiving a search engine penalty, or being dropped by the search engines completely.
A white hat SEO specialist is the only SEO specialist you should employ.