Infectious diseases represent one of the major challenges and limitation to sustainable aquaculture. They can have major impacts on animal welfare, livelihood of farmers and threaten the health of captive stocks and wild populations. Pathogens can spread through movement of live fish, fish products, water and shared equipment. Routine screenings of pathogens in aquatic animal production systems are important to minimize the risk of their introduction, transmission and spread. On suspicion of a disease during abnormal mortalities, investigation with collection of biological samples from moribund animals must take place rapidly for disease diagnostics. Quality biological sampling is a fundamental requirement for all kinds of disease diagnostic and pathogen screening work. WorldFish and partners developed this rapid guide on sampling materials required for fish disease diagnostics. It lists all the personal protective equipment, the data collection/recording/cleaning supplies and sampling materials: consumables, reagents, media and tools needed to conduct one of the six quick fish-sampling guide for disease diagnostics: 1. Wet-mount sampling guide (for ectoparasites & fungi) 2. Fish & water Microbiome sampling guide 3. Blood sampling guide 4. Bacteriology sampling guide 5. Molecular and virology sampling guide 6. Histology sampling guide