The appearance of new and the recurrence of old bacterial infections in animals, coupled with a simultaneous epidemic increase in the number of multidrug-resistant strains and accompanying diagnostic problems, causes a growing interest in alternative strategies for prevention and treatment of resultant diseases. Technologies based on therapeutic bacteriophages or various kinds of nanomaterials are very promising and increasingly applied in eradicating harmful enzootic and zoonotic pathogens. A new development in these endeavours may be the combined use of phages (particularly M13, MS2, λ and T-even phages) and nanoparticles for a synergistic effect. Mutual interactions between the two factors depend not only on the type and characteristics of a given nanomaterial and on the morphological type of the phage, but also on their quantity, ambient temperature, and time of exposure. Interactions between nanoparticles and bacteriophages are due to electrostatic effects used in creating hybrid phage-nanomaterial constructs that find application in eradicating bacterial pathogens, including drug-resistant and biofilming ones, as well as in directed drug delivery. One of the methods for creating useful phage-nanomaterial complexes is immobilisation by encapsulation. The entrapment of phages in a liposome structure promotes their replication and activity thanks to the small size and positive electric charge. Liposomal encapsulation protected them from the strongly acidic environment in the stomach, significantly prolonged the possibility of their storage, as well as increased their stability and durability in drinking water and feed without changing the sensory properties of water and feed. Phage-nanomaterial complexes can also be a very precise diagnostic tool for detecting bacterial pathogens in the environment, considerably increasing the sensitivity, specificity and rapidity of detection tests.