The aim of this research was to find relationships between complimentary advertising strategies and sponsored search advertisement (SSA) in order to formulate a model to maximise return on investment achieved from online sponsored search advertisements. The results obtained from statistical analyses of SSA campaign data showed that complimentary online and offline advertisement campaigns have various different correlations to impressions, click-through rates, number of pages visited, time spent visiting a website, bounce rate of visitors to the website, cost-per-click and number of new registrations per keyword search from visitors gained through SSA campaigns. In particular, online display advertisements were found to have a slight positive correlation with new registrations made by customers gained through a simultaneously running SSA campaign. Offline radio adverts were found to have a positive correlation with impressions gained for SSA campaigns, whilst at the same time showing a negative correlation with the number of pages viewed by website visitors obtained through the SSA campaign. Some negative correlations to SSA campaign performance were also found, with the time visitors spent viewing the website decreasing, their bounce rate increasing and the cost-per-clicks for the keywords in the SSA campaign also increasing during periods when offline radio adverts were active. Offline television adverts were found to have a negative correlation with impressions gained for SSA campaigns, as well as the click-through rate for the keywords in these SSA campaigns. Offline television adverts did however also show a negative correlation with the cost-per-clicks for keywords in the SSA campaigns. Finally, a graphical model was developed to illustrate these correlations found between complimentary advertisement campaigns and SSA performance metrics.