The introduction of the article "The ABCs of solute carriers: physiological, pathological and therapeutic implications of human membrane transport proteins" provides an overview of the solute carrier (SLC) gene series, which includes 43 families and 298 transporter genes. The article highlights the importance of transporters as gatekeepers for cells and organelles, controlling the uptake and efflux of essential compounds. Transporters are categorized into passive and active transporters. Passive transporters facilitate the passage of solutes across membranes, while active transporters create ion/solute gradients using energy-coupling mechanisms, such as ATP hydrolysis. The article also discusses the development of expression cloning and genome sequencing techniques that have advanced the identification and characterization of transporters. The "SLC mini-review series" aims to provide an overview of different types of mammalian transport systems within the SLC series, focusing on their physiological, pathological, and pharmacological implications. The article includes a list of currently approved SLC human gene symbols and their respective families.The introduction of the article "The ABCs of solute carriers: physiological, pathological and therapeutic implications of human membrane transport proteins" provides an overview of the solute carrier (SLC) gene series, which includes 43 families and 298 transporter genes. The article highlights the importance of transporters as gatekeepers for cells and organelles, controlling the uptake and efflux of essential compounds. Transporters are categorized into passive and active transporters. Passive transporters facilitate the passage of solutes across membranes, while active transporters create ion/solute gradients using energy-coupling mechanisms, such as ATP hydrolysis. The article also discusses the development of expression cloning and genome sequencing techniques that have advanced the identification and characterization of transporters. The "SLC mini-review series" aims to provide an overview of different types of mammalian transport systems within the SLC series, focusing on their physiological, pathological, and pharmacological implications. The article includes a list of currently approved SLC human gene symbols and their respective families.