In a past life, I worked as a Search Engine Optimisation consultant. It was my role to audit websites and identify improvements that would help that page rank in searches. It was an interesting job that gave an insight into the way that Google works.

It's a commonly held misconception that SEO's work against Google or somehow are trying to game the system. So-called black hat SEO is a strategy that hasn't worked since 2005 and can see your site punished for the attempt. 

Google has been working with website owners for a long time to improve the quality and performance of their websites. It's in Google's best interest for search users to find what they want. Part of their advice has been around how to engage an SEO agency. 

The video below comes Google's Developer Program Tech Lead Maile Ohye and summarises their key advice for site owners when dealing with SEO agencies:

SEO's should corroborate their advice with statements from Google

Search is not the wild west that it used to be. Instead of dodgy advice and recommendations from 15 years ago, there are lots and lots of sources of advice from Google for most SEO tactics. From domain types to backlinks, there are loads of good articles and advice directly from Google.

"Request that your SEO consultant corroborate their recommendations with documented statements from Google that support their description of each issue and their approach to resolving it."

Google has a lot of different sources for this advice. 

• Their SEO starter guide is a great starting point
• Their entire webmaster's support center is a great source of information
• The Google Webmaster's Youtube Channel has dozens of videos and even weekly live-streamed office hours that are very helpful

Recommended changes should come with an estimated business impact

Every time you change something fundamental to your strategy there is a risk. Like any other risk it is important to understand the consequences. Any changes your SEO consultant suggests should come with an expected business benefit. 

This should go beyond simply a "you'll have better rankings" but how those rankings will help influence the individuals that can drive growth for your business.

Alongside these rankings come the usual advice that I would be remiss not to outline here:

• Nobody can guarantee you rankings, avoid those who do
• Avoid tactics that try to game Google, a good rule of thumb is that all SEO work should make the website better for customers rather than just search engines.
• Be careful if a company won't explain clearly what they will do and how they will do it