Colchester manager Tony Humes will be looking for experienced players to strengthen his squad after a third successive relegation battle.
Their victory over Preston on the final day of the season saw them secure their place in League One for another season.
In 2012-13 they only finished one place above the bottom four, but last term managed to pull away to 16th place.
"We need some more experience, but we also need to keep developing our young players," Humes told BBC Essex.
"We have got to build on what we have done this season and bring in the right characters into this football club.
"What we do this summer will go a long way to dictating what we do next season and how we keep taking the club forward."
Colchester managed four wins, two draw and two losses in their final eight matches and 49-year-old Humes praised his side's resilience following the win over promotion-chasing Preston.
"I have to give credit to the players, they were brilliant," he added. "It was a tough game against a good team and the players did well.
"They have shown character and belief so many times this season and they did it again."