Modification of textile materials with nanoparticles is one of the leading procedures for obtaining antimicrobial textiles. The metal-based nanoparticles are the most common ones for antibacterial functionalization, since metals and their oxides such as gold (Au), silver (Ag), copper (Cu) or zinc (Zn) possess biological and antimicrobial properties, that are important for the development of antibacterial textiles, while also polymeric based nanoparticles can be used, for example chitosan, to encapsulate antimicrobial compounds and give functionality to the textile. The shape and size of nanoparticles have one of the most important roles in providing antimicrobial activity, since their size determines the active surface area of the particle, while the nature of the interaction between nanoparticles and textiles determines the area of application and durability of antibacterial activity. Interactions between nanoparticles and textile fibers can be physical, chemical, and of a combined nature, and in this chapter, we will give a brief overview of the most common techniques for functionalization of textile materials with nanoparticles. The physical incorporation of nanoparticles into the fiber is the most unstable since only physical deposition is not enough to maintain the durability of the antibacterial finish of the textile. On the other hand, loose connections between nanoparticles and textiles enable easier release of active agents in the surroundings, making a possible application in disposable products where immediate and strong antibacterial action is required, e.g. wound dressings. On the other hand, the chemical nature of the interaction between nanoparticles and textile materials ensures the durability of antibacterial activity since permanent chemical bonds are established. These interactions are suitable for products that may require repeatable washing and prolonged use. Combined interactions include both physical deposition and chemical attachment of nanoparticles to textile material. Which type prevails is decisive for the application of the textile product. The study of the interaction between nanoparticles and textile fibers is very important from the aspect of designing multifunctional textiles and considering the complexity of possible interactions, this area is highly present in research with growing interest of the world's scientific public. In this chapter, the future potential to expand research in this field will be outlined.