This book presents a selection of the papers presented at EUROCODE '90, the symposium on coding theory held in Udine, Italy, November 1990. It gives the state of the art on coding in Europe and ranges from theoretical top- ics like algebraic geometry and combinatorial coding to applications like modulation, real-space decoding and VLSI implementation. The book is divided into eight sections: - Algebraic codes - Combinatorial codes - Geometric codes - Protection of information - Convolutional codes - Information theory - Modulation - Applications of coding. Five of the sections are introduced by an invited contribution.