Marshalled superbly by the ever-composed Jonny Evans at the back, they have stuck rigidly to their 5-3-2 shape and thwarted the waves of Italian attacks they have had to face.
Bailey Peacock-Farrell has had to stay alive and make a few good saves, but nothing you wouldn't expect him to deal with.
Ian Baraclough has looked animated throughout on the touchline - he and his players will no doubt enjoy the half-time breather.
Post update
HT: Northern Ireland 0-0 Italy
As it stands a draw is good enough for Italy. It's also goalless between Switzerland and Bulgaria at half-time, which puts the Italians in pole position to progress to Qatar.
A big 45 minutes awaits for both sides.
Getty ImagesCopyright: Getty Images
HALF-TIME
Northern Ireland 0-0 Italy
After a whole seven seconds of additional time the half-time whistle blows.
Northern Ireland have frustrated the European Champions and we're yet to have the breakthrough.
Former Northern Ireland defender on BBC Radio Ulster
Quote Message: The Italians are frustrated. Northern Ireland are comfortable at the moment. They are having to work hard but they are holding the line so well - reading the game well, closing players down and getting their tackles in when they need to. They are defending well but it is controlled defending.
The Italians are frustrated. Northern Ireland are comfortable at the moment. They are having to work hard but they are holding the line so well - reading the game well, closing players down and getting their tackles in when they need to. They are defending well but it is controlled defending.
Post update
Northern Ireland 0-0 Italy
It's a better delivery in from Ali McCann but the Italians easily clear. Two to go until half-time.
Post update
Northern Ireland 0-0 Italy
But the corner doesn't beat the man at the front post.
Northern Ireland win a free-kick when Insigne handles the ball. They'll get another go.
Post update
Northern Ireland 0-0 Italy
Jorginho, who I genuinely forgot was on the pitch, tries a backheel in his own corner but it goes out of play.
Federico Chiesa breaks down the left and cuts inside the area. He fires in a low, powerful effort but Peacock-Farrell is equal to it and he keeps it out with his feet.
He'd drifted offside so it wouldn't have counted, but Peacock-Farrell wasn't to know that. Great stop.
It's coming straight back
Northern Ireland 0-0 Italy
Mark Sterling
BBC Sport NI at Windsor Park
Northern Ireland are having to work very hard here.
Italy are so controlled in possession and, while they have not created that many chances, they are dragging the home players from one side to another.
Ian Baraclough's men look well drilled, but you wonder just how long they can keep the hard work up for.
Josh Magennis and Gavin Whyte are also having to drop deep at times, and when the ball does go up to them it's often coming straight back at the Northern Ireland defence.
But generally it's so far, so good for Northern Ireland.
Post update
Northern Ireland 0-0 Italy
Jonny Evans is under heavy pressure but, cool as you like, takes it down on his chest, flicks the ball over the shoulder of Chiesa and he turns away from the danger.
It's mad how good he is.
All Whyte on the night
Northern Ireland 0-0 Italy
PacemakerCopyright: Pacemaker
Sandro Tonali and Gavin Whyte battle for possession during the first halfImage caption: Sandro Tonali and Gavin Whyte battle for possession during the first half
Post update
Northern Ireland 0-0 Italy
Federico Chiesa will have to peel Stuart Dallas off his back after this one. He's barely had a sniff so far.
He shows some fancy footwork to get into the area, again shadowed by Dallas, and his weak effort is straight at Peacock-Farrell.
Post update
Northern Ireland 0-0 Italy
Not to jinx it, but with 30 minutes played it's so far, so good for Northern Ireland.
Post update
Northern Ireland 0-0 Italy
The problem with Josh Magennis playing up front on his own is he can't get on the end of his monstrous throw-ins.
Stuart Dallas has a go but the visitors easily clear.
Post update
Northern Ireland 0-0 Italy
Craig Cathcart concedes a corner on the far side.
The Italians try one off the training ground but Peacock-Farrell is up and grabs the ball with ease when it eventually comes in.
Live Reporting
Andy Gray
All times stated are UK
Match of the Day Northern Ireland
HT: Northern Ireland 0-0 Italy
Watch the highlights of the World Cup qualifier between Northern Ireland and Italy on BBC One NI and the BBC iPlayer tonight.
Even if it all goes belly up after the restart you can still enjoy the first 45 minutes.
Post update
HT: Northern Ireland 0-0 Italy
Evans in charge at the back for NI
HT: Northern Ireland 0-0 Italy
Mark Sterling
BBC Sport NI at Windsor Park
That's a good half for Northern Ireland.
Marshalled superbly by the ever-composed Jonny Evans at the back, they have stuck rigidly to their 5-3-2 shape and thwarted the waves of Italian attacks they have had to face.
Bailey Peacock-Farrell has had to stay alive and make a few good saves, but nothing you wouldn't expect him to deal with.
Ian Baraclough has looked animated throughout on the touchline - he and his players will no doubt enjoy the half-time breather.
Post update
HT: Northern Ireland 0-0 Italy
As it stands a draw is good enough for Italy. It's also goalless between Switzerland and Bulgaria at half-time, which puts the Italians in pole position to progress to Qatar.
A big 45 minutes awaits for both sides.
HALF-TIME
Northern Ireland 0-0 Italy
After a whole seven seconds of additional time the half-time whistle blows.
Northern Ireland have frustrated the European Champions and we're yet to have the breakthrough.
'Frustrated' Italians
Northern Ireland 0-0 Italy
John O'Neill
Former Northern Ireland defender on BBC Radio Ulster
Post update
Northern Ireland 0-0 Italy
It's a better delivery in from Ali McCann but the Italians easily clear. Two to go until half-time.
Post update
Northern Ireland 0-0 Italy
But the corner doesn't beat the man at the front post.
Northern Ireland win a free-kick when Insigne handles the ball. They'll get another go.
Post update
Northern Ireland 0-0 Italy
Jorginho, who I genuinely forgot was on the pitch, tries a backheel in his own corner but it goes out of play.
Corner Northern Ireland - the noise goes up!
Post update
Northern Ireland 0-0 Italy
Don't we all!
Post update
Northern Ireland 0-0 Italy
Five minutes to go until half-time.
GREAT SAVE!
Northern Ireland 0-0 Italy
Federico Chiesa breaks down the left and cuts inside the area. He fires in a low, powerful effort but Peacock-Farrell is equal to it and he keeps it out with his feet.
He'd drifted offside so it wouldn't have counted, but Peacock-Farrell wasn't to know that. Great stop.
It's coming straight back
Northern Ireland 0-0 Italy
Mark Sterling
BBC Sport NI at Windsor Park
Northern Ireland are having to work very hard here.
Italy are so controlled in possession and, while they have not created that many chances, they are dragging the home players from one side to another.
Ian Baraclough's men look well drilled, but you wonder just how long they can keep the hard work up for.
Josh Magennis and Gavin Whyte are also having to drop deep at times, and when the ball does go up to them it's often coming straight back at the Northern Ireland defence.
But generally it's so far, so good for Northern Ireland.
Post update
Northern Ireland 0-0 Italy
Jonny Evans is under heavy pressure but, cool as you like, takes it down on his chest, flicks the ball over the shoulder of Chiesa and he turns away from the danger.
It's mad how good he is.
All Whyte on the night
Northern Ireland 0-0 Italy
Post update
Northern Ireland 0-0 Italy
Federico Chiesa will have to peel Stuart Dallas off his back after this one. He's barely had a sniff so far.
He shows some fancy footwork to get into the area, again shadowed by Dallas, and his weak effort is straight at Peacock-Farrell.
Post update
Northern Ireland 0-0 Italy
Not to jinx it, but with 30 minutes played it's so far, so good for Northern Ireland.
Post update
Northern Ireland 0-0 Italy
The problem with Josh Magennis playing up front on his own is he can't get on the end of his monstrous throw-ins.
Stuart Dallas has a go but the visitors easily clear.
Post update
Northern Ireland 0-0 Italy
Craig Cathcart concedes a corner on the far side.
The Italians try one off the training ground but Peacock-Farrell is up and grabs the ball with ease when it eventually comes in.
Post update
Northern Ireland 0-0 Italy
The GAWA bringing the noise.