The aims of this study were to compare handwriting and writing capabilities as well as executive functions (EF) and developmental and functional characteristics of adolescents with and without dysgraphia and to find the predictors of their writing capabilities. Eighty adolescents, aged 13-18, 40 with dysgraphia, and 40 matched controls, copied a paragraph and wrote an essay on paper affixed to a digitizer supplying objective handwriting process measures (Computerized Penmanship Evaluation Tool-ComPET). Content quality was evaluated using the Six Trait Method. Furthermore, for measuring EF, participants completed the Behavior Rating Inventory of Executive Function-Self-Report (BRIEF-SR), and performed tasks from the WebNeuro. Developmental and functional abilities were measured using the Adult ADHD Self-Report Scales (ASRS v.1.1) and the Adult Developmental Coordination Disorder Checklist (ADC), together with parent questionnaires. Developmental History and Child Evaluation Checklist (CHECK A + B).   Significant group differences were found for the handwriting kinematic measures and written content capabilities, executive control domains, attention, coordination and functional abilities. Forty-three percent of the variability of mean stroke duration and 63% of the variability of the written content quality were predicted by EF and developmental and functional measures. The Conclusions will discuss the theoretical and the clinical implications of the research.