Research has proven that high rankings in search engine results are imperative for the success of mission critical websites. This poster reports on empirical research having been done on the identification of webpage design factors which positively influence the visibility of a webpage to search engine crawlers. A number of theoretical models were identified, all attempting to classify and rank these elements. Some of these models were based on empirical work. Furthermore, a trustworthy model of SEO practitioner viewpoints was found, and a scoring system designed to allocate point values to all the elements identified and ranked in these models. Equal scores were given to each of the academic and the practitioner models. Both sets of models produced a large number of positive and negative elements. In many cases, different titles were used for the same element. In some cases no ranking was done, and the scoring system had to be adapted to cater for these cases. Eventually a single ranking series was produced, where a higher element score indicated a more positive ranking effect. A total of 17 factors were identified. The top six had a noticeably higher score than the remainder, which indicates that a designer should apply more focus to those six than to the remaining 11. The most important element to implement is a high quantity and quality of inlinks, where the designer attempts to establish a set of highly ranked hyperlinks pointing to a certain website. Second on the list is the correct use of body keywords. Similarly, a designer should load a webpage with a large number of relevant keywords and phrases. It is imperative that website designers be aware of this ranking, and they should ensure that they implement most of these elements in a mission critical website design.