This article presents a review of current methods for production of metallic open-cell porous materials through space holders. The methods are divided into two major groups: on the basis of sintering and using liquid phase processing. Details about technologies are given, and their relations to structure parameters of obtained materials are discussed. Methods with 11 different space holders are described. The space holders could be metallic or nonmetallic (organic and inorganic) materials which could be leached or burned depending on removal technique. It is concluded that the flexible application of different space holders offers opportunities for obtaining large variety of metallic porous structures. A new line of development should be elaboration of complex techniques for production of porous structure with graded pore size and/or porosity which will meet various engineering requirements and will open new possibilities for applications as functional and structural elements. The next part of this work is devoted to the structure, the properties, and application of the open-cells porous materials obtained through space holders.