Sporting a mix of blue, yellow, white, green and black, the unmistakable Blue Tit reflects the colours of a planet affected by a burgeoning human population. Fortunately, Blue Tits are adapting well to modern humanity, taking advantage of our propensity to feed birds in our gardens and provide boxes for them to nest in. In turn, this feisty little species provides an excellent model for biological research. This book is the result of a personal quest by author Martyn Stenning to bring together a range of discoveries into one accessible volume. _The Blue Tit_ begins by inviting readers into the intimate lives of these birds as they attempt to reproduce, describing the many challenges they face when rearing their offspring. The story moves on to the fluid state of Blue Tit classification across the native Palearctic range, before progressing into population structure, lifetime ecology and an exploration of factors that determine breeding success. It culminates with an in-depth look at research over the years, followed by a selection of personal anecdotes and an overview of Blue Tit appearances in folklore and poetry. This book provides a definitive record of the biology and ecology of one of our most popular, intelligent and charismatic birds.