Objectives: The objectives were to assess trends over the past 10 years in vaccination coverage rates (VCR) among adolescents in France aged 14-15 years, factors influencing decisions to vaccinate, and mothers' opinions on adolescent vaccination., Patients and Methods: The 'Vaccinoscopie' internet survey is completed each year by mothers of adolescents, with questions about vaccinations received by their children, and their attitudes and barriers to vaccination. The 2012 to 2021 surveys were analyzed in this study, including data from 1500 adolescents in 2012 and 1000 adolescents each year from 2013 to 2021., Results: None of the adolescent VCR targets were met, despite significant increases since 2012 for vaccines with the lowest coverage rates and vaccines with high but insufficient coverage i.e., meningococcal C (28.7% to 60.8%), HPV in girls (14.2% to 40.8%), hepatitis B (31.6% to 47.3%) and pertussis (76.3% to 91.0%). Physicians remained the primary source of vaccination information for 90.4% of mothers, and their advice had a real impact on improving VCRs. Adolescents were increasingly involved (40.1%) in decisions about vaccination. Depending on the vaccine, over 80% of mothers currently consider adolescent vaccination as useful or essential. Since 2017, they also feel better informed., Conclusions: Low and under-target VCRs put adolescents at risk of severe disease, and do not enable herd immunity or reduced transmission to other vulnerable age groups to be accomplished. Healthcare professionals must take every opportunity to check adolescents' vaccination status and recommend catch-up vaccines where applicable. Vaccination in schools should be considered., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [AM, RC, JPS, PG and JG are members of the Vaccinoscopie scientific board (put in place by IDM Families and funded by GSK). AM received consulting fees for his participation in this board, honoraria for presentations from GSK and MSD and support for attending meetings from Pfizer. RC participated in scientific boards and symposia organized by Sanofi-Pasteur, was invited to congresses and symposia by Pfizer and participated in scientific boards and symposia from Merck. JPS declares receiving personal payments from GSK, and from Sanofi in the past 36 months. JPS also declares being member of the board of the French National Scientific Society and being editor-in-chief of Infectious Diseases Now. PG is the founder of IDM Families. JG received, from GSK, personal payment for his work on the current manuscript as well as payment for other educational activities (lectures, presentations, speaker bureaus, manuscript writing or educational events) on the past 36 months. AG and LM are employed by GSK and hold shares in GSK. MD declares no financial and non-financial relationships and activities. The authors declare no other financial and non-financial relationships and activities.], (Copyright © 2024. Published by Elsevier Masson SAS.)