Table-topping Brighton produced their sixth win in seven league games with a goal in each half from Tomer Hemed and Dale Stephens to sink rock-bottom Rotherham United.
Substitute Jonson Clarke-Harris pulled a late goal back for the Millers who have now lost five of their seven matches in the Championship.
The Seagulls, who survived six minutes of added time, were good value for their victory.
The hosts started well and Israeli midfielder Beram Kayal put a near post header wide from a corner by Stephens.
Brighton broke the deadlock in the 26th minute when Israel international striker Hemed hit his fifth goal of the season from close range.
A mistake by German defender Uwe Huenemeier gave Millers midfielder Chris Maguire a clear sight of goal just after the break, but he wastefully put the ball over.
Rotherham’s chances of taking something from the game received a huge blow when Stephens doubled Albion’s lead after 67 minutes, the former Charlton man finding the bottom left-hand corner with a first-time shot from 20 yards.
Clarke-Harris promptly reduced the deficit four minutes later by heading in a Maguire free-kick.
Brighton: Stockdale, Saltor, Greer, Hunemeier, Bong, March (Rosenior 89), Kayal, Stephens, Murphy, Hemed (Ince 80), Baldock (Zamora 69). Unused substitutes: Maenpaa, Dunk, Forster-Caskey, Manu.
Rotherham: Camp, Buxton, Rawson, Collins, Mattock, Maguire, Smallwood (Halford 79), Newell, White (Danny Ward 46), Odjidja-Ofoe, Derbyshire (Clarke-Harris 60). Unused substitutes: Ledesma, Green, Collin, Andreu.
Ref: James Linington (Isle of Wight).