Adecco Group, the worldwide leader in Human Resource services, today announced results for the first quarter of 2011. Revenues in Q1 2011 were up 24% or 18% organically, to EUR 4.9 billion. The gross margin was 17.4%, down 60 bps versus the prior year and down 80 bps organically. SG&A increased by 6% on an organic basis. The Q1 2011 EBITA margin before integration costs was 3.6%. DSO were 54 days in Q1 2011 unchanged compared to the prior year.