This is a continuation of a series of website marketing checklists. Check out all Web Marketing Checklists in this series.

What this is about: This list covers in-site search, what features should be included, what is expected by visitors and how the results should be laid out.

Why this is important: Site search is an important element of on-site usability. Both in its ability to help visitors find the information they are looking for, or by being absent if it doesn't produce accurate results. Site search must be able to improve the visitor's experience in your site, otherwise it does more harm than good.

What to look for:

• Located in top-right corner: The typical place for site search is in the top right corner or middle of the top of the page. If it's where it is expected to it'll get used.
• Search not case sensitive: Don't make your search sensitive to caps or no caps, default all searches to all lowercase.
• Properly labeled as "search": The search box needs to be properly labeled so visitors know what it is.
• Link to "advanced search": If you can provide advanced search options include a link to it at or near the search box.
• Forgiving of misspellings: Search results should be able to account for misspellings of keywords and product names.
• Shows similar products: Search should not just return the exact results of the products searched for but also return results with similar products.
• Shows related items in results: Results should also produce results with non-similar but related products that the visitor might also be interested in.
• No "no products found": Never return empty results. Site search should always be able to produce some kind of result.
• Provide refinement options: If search produces too many, or too few results, provide options to refine the search for the visitor.
• Provide alternate spellings: Seek to correct misspelled products, brand names or other keywords.
• Provide links to relevant pages: Site search results pages are a good opportunity to provide generic links to other relevant portions of the site such as Help pages and other helpful resources.
• Show search string in results: The results should clearly indicate the actual search string used, preferably in the page heading.
• Don't place results in tables: Avoid tabling the results as in non-traditional browsers this can create confusion to the visitor.
• Display exact matches first: Exact matches should be displayed first at the top of the results.
• Display close matches second: Any results that are not exact matches should come after those that are.
• Bold query words in results: Bold or highlight the query as it appears in the results.
• Display titles with descriptions: If possible, display both a title and description with each result link.
• No more than 20 results p/ page: Don't allow search to produce more than 20-25 results at a time.
• Option to increase result p/ page: Provide visitors an option to easily increase the number of results displayed per page.
• Link to additional results pages: Provide links to second, third and more results pages as needed.

Did I miss anything? Add to this list with your comments below.