Ole Gunnar Solskjaer says any signings Manchester United make this summer must fit the culture and history of the club.
United finished an underwhelming season with a 2-0 defeat to Cardiff at Old Trafford on Sunday, a result which saw them finish sixth in the Premier League and 32 points behind champions Manchester City.
After recovering from their worst start to a league campaign for 28 years when Solskjaer replaced the sacked Jose Mourinho in December, United's season deteriorated from March onwards as they won just two of their final 12 fixtures in all competitions.
As Solskjaer prepares for arguably United's most important summer since the retirement of Sir Alex Ferguson, the Norwegian says he is actively scouting the transfer market for players who fit the mould and traditions of the club.
"You have to have a certain kind of attitude about you to make you a Manchester United player," Solskjaer told United's official app. "You have got to have the qualities and our fans want to see exciting players.
"Of course we want to get up from our seats. We want to see defenders who defend like they're doing it for their lives, that's the most important thing.
"We've tried to educate our players and our kids to be proper people. In my view, the best players have always been the best people.
"It's always been in our culture. You have to have that work ethic and we're scouting the market, trying to find the right ones."
Solskjaer won 14 of his 19 matches in interim charge before being appointed permanent boss in March. Despite a huge dip in results, he told fans to stay patient and promised them he will do the job to the best of his ability in an attempt to return the club to former glories.
"I'm excited by the whole project," he added. "I know it's a great responsibility being in charge of this great club. It's a big responsibility, but the only thing I can promise is I will do it to the best of my ability.
"Keep supporting the team as you've always done. Keep believing that when we come back, we'll give everything to get back to where we belong. Next season, we'll start afresh and I can't wait to get it going."
United launch Treble-inspired kit
Meanwhile, Manchester United have launched their new home kit for the 2019/20 season, which pays homage to the Treble the club won during the 1998/99 campaign.
United remain the only English club to have won the Premier League, FA Cup and Champions League in the same season. The shirt has the numbers '90+1' and '90+3' printed on the sleeves; a reference to the minutes in which Teddy Sheringham and Ole Gunnar Solskjaer scored in the dramatic 2-1 win over Bayern Munich to secure the European title.
The dates of the FA Cup final win over Newcastle and the game against Tottenham that sealed the league title are also printed on the bottom of the shirt.
The home kit features the traditional red shirt, white shorts and black socks, while the goalkeeper strip is purple, in a reference to the kit worn by Peter Schmeichel during the Treble-winning season.