Introduction: frailty is a dynamic syndrome and may be eversible. Despite this, little is known about trajectories or transitions between different stages of frailty. Methods: a systematic review was conducted, selecting studies reporting frailty trajectories or transition states for adults in any settings in European ADVANTAGE Joint Action Member States. Results: only three papers were included. Data were from longitudinal community based cohorts in the United Kingdom, Netherlands and Italy. The English study investigated the effect of physical activity on the progression of frailty over a 10-year period. Two presented data on the proportion of participants experiencing at least one frailty transition over time (32.6% in the Italian sample aged ≥ 65 years followed for 4.4 years; 34.3% in the Dutch sample aged 65-75 years, followed for 2 years). Conclusions: data on frailty trajectories and transition states were limited and heterogeneous. Well-designed prospective studies and harmonized approaches to data collection are now needed.