The present book constitutes and describes about some most commonly occurring helminths (trematode, cestode and nematode) parasite infections of domestic animals that are encountered under the field conditions. A brief morphological description of the parasites and their important stages from identification point of view is followed by their pathogenic effects, diagnosis, treatment, and prophylaxis and control measures. During my long association with field veterinary professionals through teaching and training courses on helminth parasite infections of domestic animals, I felt that such handbook on the subject would be of immense help and serve as ready reference to refresh their memories on the subject.