Pay Per Click (Adwords) advantages

Search Engine Optimisation advantages

Fast to implement.

SEO costs decrease over time.

Highly targeted traffic on your search terms on the major search engines.

Credibility - 'earning' the ranking rather than paying the highest bid. Research shows users prefer to click on organic search results than "Sponsored Results".

You only pay for users that click through your listing and arrive at your site.

Improvements to your website made from a search engine perspective usually result in a more user-friendly website.

Complete control of what keywords you want to bid on and no limit to the number of keywords.

A well optimised website can appear across multiple search engines and search markets, at no extra cost.

Complete control of budget - decide how much you want to bid for a keyword and your
total or monthly spend cap.

Once good search engine rankings are achieved, as long as optimisation is ongoing and monitored then the rankings acquire a "snow ball" effect, increasing over time.

Complete control of what text the listing shows - as long as it meets the engines copy and relevancy specifications.

Good for seasonal activity - immediate start and stoppage.

Testing new keywords/text copy/bid caps easy to implement and measure.