Repeatable behavioural variation within individuals that is consistent over time and across contexts is often defined as non-human animal personality. Individuals may be classified as having a shy or bold personality. Shy individuals typically react to unfamiliar situations with reactivity or avoidance and bold individuals with proactivity or aggression. When studying a population, accounting for variation in boldness may for instance prevent sample biasing or help explain observed trade-offs or non-optimal behaviour. Relationships between fitness and personality may exist in many populations but previous studies have studied only one or a few behavioural traits and the results differ substantially. This study explored possible relationships between reproductive success or survival during the breeding season and behavioural traits recorded in the wild in a population of great tits, Parus major, and is the first to obtain results with as many recorded behavioural traits for the same bird. It is unclear what is maintaining variation in personalities in a population but one explanation may be that the personalities have equal fitness over time because a trade-off between survival and reproductive success exists. Another explanation may be that all individuals exhibit the best possible behavioural type given their condition but one phenotype will be superior and have both higher reproductive success and survival. To determine which explanation was most likely, measured behavioural traits were classified as either bold or shy using previous studies results or logic reasoning. Earlier studies indicated that bold birds had higher reproductive success than shy birds, which was supported by the present study. However, no relationship between survival during the breeding season and behaviour was obvious from the previous or current study, which made the determination of whether one explanation was more likely than the other problematic. Further studies should use data from several years as the effect of personality may vary between years or seasons, test repeatability for more traits to determine whether they represent personality, and develop and use more standardised traits. In addition to age, sex and breeding time more confounding variables is probably also important to account for, for instance temperature, weather conditions, date and time of day.