TRANSACTION AND INTEGRATION On June 1, 2010, Invesco acquired from Morgan Stanley its retail asset management business, including Van Kampen Investments (the "acquired business" or the "acquisition"). Transaction and integration activities related to the acquisition were completed mid-year 2013. During the year ended December 31, 2013 , the company incurred $3.2 million ( 2012 : $8.2 million , 2011 : $29.4 million ) of transaction and integration costs ( $1.9 million , $5.1 million and $18.2 million net of taxation, respectively). Transaction and integration costs include charges related to prior acquisitions and do not represent ongoing costs of the fully integrated combined organization. They include legal, regulatory, advisory, valuation, integration-related employee incentive awards and other professional or consulting fees, general and administrative costs, including travel costs related to the transaction and the costs of temporary staff involved in executing the transaction, and post-closing costs of integrating the acquired business into the company's existing operations including incremental costs associated with achieving synergy savings. Additionally, transaction and integration expenses include legal costs related to the defense of legal challenges to auction rate preferred securities redemptions with respect to various closed-end funds included in the acquisition. See Note 18 ,  Commitments and Contingencies  for additional information. The following table presents acquisition-related and integration-related charges incurred during the period. For the year ended December 31, $ in millions 2013 2012 2011 Integration-related charges: Staff costs   0.1 2.8 Technology, contractor and related costs 0.1 0.6 11.0 Professional services 3.1 7.5 15.6 Total integration-related charges 3.2 8.2 29.4 Total transaction and integration charges 3.2 8.2 29.4