The CCP4 software suite is a collection of programs and associated data and software libraries used for macromolecular structure determination by X-ray crystallography. It is designed to be flexible, allowing users to achieve their aims through various methods. The suite includes programs from diverse sources but is connected by standard file formats, data objects, and graphical interfaces. The CCP4 suite has evolved significantly over the past 30 years, with continuous growth and the addition of new programs. It includes automation pipelines such as xia2, CRANK, MrBUMP, and BALBES, which aim to automate large sections of the structure solution process. The suite also includes a graphical user interface, ccp4i, which provides task interfaces to help users prepare run scripts and offers tools for organizing data. The CCP4 suite includes a wide range of programs for data processing, experimental phasing, molecular replacement, phase improvement, automated model building, refinement, and validation. The suite also includes molecular-graphics programs for generating publication-quality images and movies. The CCP4 suite is supported by a variety of utilities for format conversion and analysis. Future plans for the CCP4 suite include enhancing its functionality related to small molecule data, improving the user interface, and making more CCP4 functionality available via the web. The CCP4 suite is a community-based resource that supports a wide range of researchers and aims to play a key role in the education and training of scientists in experimental structural biology.The CCP4 software suite is a collection of programs and associated data and software libraries used for macromolecular structure determination by X-ray crystallography. It is designed to be flexible, allowing users to achieve their aims through various methods. The suite includes programs from diverse sources but is connected by standard file formats, data objects, and graphical interfaces. The CCP4 suite has evolved significantly over the past 30 years, with continuous growth and the addition of new programs. It includes automation pipelines such as xia2, CRANK, MrBUMP, and BALBES, which aim to automate large sections of the structure solution process. The suite also includes a graphical user interface, ccp4i, which provides task interfaces to help users prepare run scripts and offers tools for organizing data. The CCP4 suite includes a wide range of programs for data processing, experimental phasing, molecular replacement, phase improvement, automated model building, refinement, and validation. The suite also includes molecular-graphics programs for generating publication-quality images and movies. The CCP4 suite is supported by a variety of utilities for format conversion and analysis. Future plans for the CCP4 suite include enhancing its functionality related to small molecule data, improving the user interface, and making more CCP4 functionality available via the web. The CCP4 suite is a community-based resource that supports a wide range of researchers and aims to play a key role in the education and training of scientists in experimental structural biology.