Loci communes or Loci communes rerum theologicarum seu hypotyposes theologicae (Latin for Common Places in Theology or Fundamental Doctrinal Themes) was a work by the Lutheran theologian Philipp Melanchthon published in 1521^[1] (other, modified editions were produced during the life of the author in 1535, 1543 and 1559). Martin Luther said of it, "Next to Holy Scripture, there is no better book,"^[2] and its existence is often given as a reason that Luther never wrote a systematic theology of his own. In an overture to the English king, Henry VIII, to gain the English crown as converts to Lutheran protestantism, Melanchthon provided a dedication to the king in one of his printed editions.^[3]

The book lays out Christian doctrine by discussing the "leading thoughts" from the Epistle to the Romans, and they were intended to guide the reader to a proper understanding of the Bible in general.