Companies should use agencies sparingly and outsource the specialist aspects of search marketing campaigns where agencies can really add value. Often it’s wiser to engage an agency for a one off project or occasional consultancy than go to the expense of a retained service over a long period of time.

There is little point outsourcing your paid search strategy because this activity requires a detailed knowledge of your product and service offerings. An outside agency will need large amounts of guidance and constant monitoring from you to execute a half-decent PPC strategy and will probably leave you wishing you’d just spent the time doing it yourself. PPC adverts need to closely reflect the marketing messaging on your site, so it’s best to maintain in house control of both.

Offsite SEO is time consuming and specialised. A specialist SEO agency will be able to provide both the man power and the creativity necessary to encourage up-take of relevant links to your site. Broadly speaking it’s better to get agencies to do this “off-site” work and let your in-house developers handle the on-site side of things, because they’re closer to the metaphorical coal-face.

When choosing an agency you should take a good look at their existing clients and case studies:

SEO: Where are their clients ranking in natural search for competitive keyword terms? Do some Google searches on the senior SEO strategists. If they regularly blog or present conferences about SEO, it’s a good sign that they stay up to speed with the latest industry trends, which is crucial in such an ever changing field of expertise.

Paid: Are their clients’ paid search adverts well worded, with relevant copy in regard to the search query, and do they follow best practise for ad text? Without well structured and targeted paid search a company will pay substantially more than necessary. All too often you will see generic adverts with little relevance to your query because the agency has not invested enough time in structuring a well thought out and targeted campaign.

Social Media: How many friends do their existing clients have on Facebook compared to their competition? Do they have many Twitter followers and are you engaged by what has been tweeted? It’s wise to conduct a bit of research into what’s being said about the agency in online forums. You will often get genuine feedback on third party experience of the agency in question, which is invaluable when parting with hard earned cash regardless of reason.

Have they won any credible industry awards for campaigns they have conceived and realised? This is an excellent way to assess how well the agency tackles issues and the creativity that has gone into projects. Ask the opinion of fellow online marketing managers you know. There is nothing better than getting a trusted recommendation.

How to get the best out of them

Even if you choose to outsource all of your online marketing to a specialist agency, it’s no excuse for not developing your own knowledge so you can get the most out of your agency and have an informed view of the strategies they propose and evaluate their performance.

Look for an SEO specialist and get them to set realistic targets that you can hold them to ahead of signing any contract. Companies need to make sure they have a senior person working on their account since in this very new industry experience counts for a lot.

Something to watch out for is agencies who offer to do your SEO work free of charge, provided they are given your PPC contract. In this instance you are likely to get what you’re paying for, with little to no work done on your SEO campaign. As I’ve said before, you’re better off doing PPC in-house and out sourcing your “off-site” work.