Search engine optimisation (SEO) is used to improve the visibility of a website or web page in search engines via the 'natural' or unpaid search results. Very few of us look beyond the first few results we get from a search engine. The higher a site appears in the search results list, the more likely we are to click on it. So what are the tricks of the trade that content publishers use to lift pages higher in search results? To answer this question Simon Smith is joined by Duncan Bloor, a BBC search specialist; Jo Pham, a BBC producer and Doug Platts, head of natural search at iCrossing, a digital agency specialising in search.