Affected by Google Panda or Penguin updates?
Here is a detailed case study of how to recover search position from the recent Google Panda and Penguin updates, which targeted the legacy of indiscriminate link building that some SEO agencies pursued
Recently we have taken on projects where the client's site has been subject to penalties incurred from Google's recent Panda and Penguin algorithm updates, which targeted unnatural or indiscriminate link building activity, predominantly undertaken by SEO agencies as a quick and dirty alternative to a recommended high quality content marketing and outreach strategy.
Here is a great, detailed case study from expert SEO consultant Gary Viray on steps taken to successfully recovering a client in a similar situation from the same drop in Google search traffic. It is a really practical explanation of steps to recovery with corresponding examples from the case study