ZX Spectrum Next truly brings Speccy to the next millenium. Faster processor, expanded memory, sprites, advanced graphics modes etc. This book developed from my notes as I was learning these new technologies. As such, it can be used as a learning tool for beginner, but also as reference for advanced programmer. The book is divided into three parts. First it looks into Zilog Z80, history, registers, flags, timing and interrupts and less know features like undocumented effects and instructions. Second part is devoted to ZX Spectrum Next. It explains new technologies from perspective of assembler developer. Many are accompanied with example code or even fully working companion projects. Topics covered: Ports Memory Mapping ULA Layer 2 Tilemap Sprites Interrupts Keyboard The last part of the book lists all Z80 and Next extended instructions. It attempts to cover them from multiple perspectives: quick list with basic information, detailed list with descriptions, effects, timing tables and sorted lists of all variants with their hex opcodes.