Operating income at Simon & Schuster's global business leapt 39.5% in 2010, despite a slight decline in sales.
For the 12 months ending 31st December, operating income at S&S was $64.6m (£40.1m). Revenue declined slightly from $793.5m (£493.0m) to $790.8m (£491.4m).
Parent company CBS said strong digital sales, double those in 2009, were offset by lower physical book sales in a "soft" market. It said its increase in profit reflected the impact of cost-saving measures and lower production costs.
In the three months to 31st December, publishing sales were up 5% to $231.7m (£144.0m). CBS said this reflected a growth of 117% in digital sales.
Operating income at S&S was up 32.6% to $17.9m (£11.1m).
At CBS, full year sales were up 8% to $14.06bn (£8.7bn) and operating income was up from $243.5m to $616.7m.