SDL, the FTSE 250-listed translation and communications software firm, has named Director David Clayton as its new Non-Executive Chairman, the company said on Wednesday morning.Clayton will take over the role on July 1st from Mark Lancaster who has been running as both Chief Executive Officer (CEO) and Chairman since November after SDL's previous CEO John Hunter left to pursue other business interests.SDL said: "The appointment continues the company's process of developing best governance practice and allows Mr Lancaster to focus entirely on his role as CEO during an important stage of the company's development."The move follows the company's performance in its first quarter (ended March 31st) which was slightly behind management expectations due to subdued trading in the Technology segment. Nevertheless, the company said in April that it remained confident for the outlook for the full year.Clayton has been a Director at the company since December 2009 and Senior Independent Director since April 2012. He has held executive roles at a number of international technology firms including Sage.Commenting on his appointment, Lancaster said: "David has extensive experience of the software industry and listed companies. His appointment comes at an important point in SDL's development.  "He has a thorough understanding of SDL's business and strategy and I look forward to working with him to fulfill the long-term potential of the company."