Adults with cerebral palsy (CP) experience difficulties in their participation. Knowledge on the course of difficulties in participation of individuals with CP emerging into adulthood could provide insight in this stage of participation development. We aim to describe the course of difficulty and independence in participation of individuals with CP from adolescence into the early thirties.

One hundred and fifty-one individuals with CP (63% male, Gross Motor Function Classification System [GMFCS] levels I-IV, without Intellectual Disability [ID]), of whom 98 completed a 13-year follow-up measurement, were included (379 observations, age range 16–34 years). Six domains of the Life Habits questionnaire were used up to three times biyearly and at 13-year follow-up. Scores (range 0–10) reflect difficulty and assistance in participation in housing, education & employment, interpersonal relationships, recreation, community life, and responsibilities. Multilevel models were used to determine the course of difficulty in participation by GMFCS level.

Despite high average participation levels, 41 to 95% of adolescents and young adults with CP experienced difficulty. Difficulty in participation increased in most life areas in the mid- and late twenties, and for housing and interpersonal relationships from age 16 years onwards. In adolescents with GMFCS III and IV, difficulty in recreation and community life decreased up to age 23 years. Mean category scores reflected independent functioning (score>5.56) in all GMFCS levels over age 23 years.

Difficulty in participation of individuals with CP without ID increases in their mid- and late twenties. Notwithstanding high participation levels on average, a substantial part of individuals with CP emerging into adulthood experience difficulty in participation. Systematic screening and timely support may improve the development of optimal participation of young adults with CP.