Gregory of Nyssa provides a concise and accessible introduction to the thought of this early church father with new translations of key selections of his writings. Anthony Meredith presents a diverse range of Gregory's writings: his contribution to the debates of the period about the nature of God in argument with a form of extreme Arianism; his discussion of the nature and work of the Holy Ghost, against the so-called 'Spirit fighters'; his defence of the humanity of Christ against those who denied it (notably Apollinarius); the nature of fate and other philosophical issues.