Ross County overcame Hibernian to remain unbeaten in 2013 and consolidate their Scottish Premier League position.
Ivan Sproule scored against his former club to give County the lead nine minutes before the break.
The winger was a persistent threat to the Hibs defence, with Rocco Quinn also had a couple of strikes at goal.
Hibs offered little in attack, with Leigh Griffiths restricted to long-range efforts on a frustrating evening for the visitors.
County remain tenth but are now 14 points clear of bottom club Dundee, while fourth-place Hibs are now just a point above St Johnstone.
The Leith men tried hard to keep the ball on the deck amid windy conditions and Griffiths' low shot tested Mark Brown just before the quarter-hour mark.
The hosts gradually began to take control and Ross Quinn was unsuccessful with a drive over the bar before Sproule began to trouble his old team-mates.
The winger had a couple of efforts blocked by Williams, the second after being sent through by Iain Vigurs' incisive pass.
Hibs did not heed the warning of that combination and Sproule breached the defence again to round the goalkeeper and touch home.
An effort by Quinn was gathered by Williams at the second attempt as County sought to double their lead at the start of the second half.
A long-range shot by Gary Deegan which went straight into the arms of Brown typified the kind of night Hibs were having.
Sproule was withdrawn midway through the second half with a hamstring strain and German forward Steffen Wolfarth made his Ross County debut as a substitute.
But there was to be no more scoring at Victoria Park, with referee Bobby Madden seeing nothing amiss in the County penalty box as Griffiths tangled with Mihael Kovacevic in injury time.