This review presents a comprehensive overview of spectral density functional theory (SDFT) and its applications in electronic structure calculations of strongly correlated materials. The authors discuss the basic ideas and techniques of SDFT, which are crucial for understanding the behavior of materials with strong electron correlations. They illustrate the method with examples where interactions play a dominant role, such as systems near metal-insulator transitions, volume collapse transitions, and systems with local moments. The review covers several key topics: 1. **Introduction**: Discusses the importance of ab initio description in strongly correlated solids and the challenges of traditional methods like model Hamiltonians and density functional theory (DFT). 2. **Spectral Density Functional Approach**: Explains how SDFT combines with DFT to provide a more accurate description of strongly correlated materials. 3. **Techniques for Solving the Impurity Model**: Reviews various methods for solving the quantum impurity problem, including perturbation expansions, quantum Monte Carlo, and mean-field approaches. 4. **Application to Materials**: Details specific applications of SDFT to materials with metal-insulator transitions, volume collapse transitions, and systems with local moments. 5. **Outlook**: Highlights future directions and the potential of SDFT in material design and discovery. The authors emphasize the importance of combining SDFT with electronic structure methods to address the unique challenges posed by strongly correlated electron systems, such as the presence of both quasiparticle and Hubbard bands. They also discuss the practical implementation of SDFT, including the construction of functionals and the use of computational tools.This review presents a comprehensive overview of spectral density functional theory (SDFT) and its applications in electronic structure calculations of strongly correlated materials. The authors discuss the basic ideas and techniques of SDFT, which are crucial for understanding the behavior of materials with strong electron correlations. They illustrate the method with examples where interactions play a dominant role, such as systems near metal-insulator transitions, volume collapse transitions, and systems with local moments. The review covers several key topics: 1. **Introduction**: Discusses the importance of ab initio description in strongly correlated solids and the challenges of traditional methods like model Hamiltonians and density functional theory (DFT). 2. **Spectral Density Functional Approach**: Explains how SDFT combines with DFT to provide a more accurate description of strongly correlated materials. 3. **Techniques for Solving the Impurity Model**: Reviews various methods for solving the quantum impurity problem, including perturbation expansions, quantum Monte Carlo, and mean-field approaches. 4. **Application to Materials**: Details specific applications of SDFT to materials with metal-insulator transitions, volume collapse transitions, and systems with local moments. 5. **Outlook**: Highlights future directions and the potential of SDFT in material design and discovery. The authors emphasize the importance of combining SDFT with electronic structure methods to address the unique challenges posed by strongly correlated electron systems, such as the presence of both quasiparticle and Hubbard bands. They also discuss the practical implementation of SDFT, including the construction of functionals and the use of computational tools.