Aseptic techniques prevent the contamination of a sample from other bacteria or pathogens. It is important to do this to ensure that the sample we are dealing with remains pure. Microorganisms are in the environment all around us, and are easily transfered to samples we are working with. A contamination could result in the production of a different result to a test, for example many different bacterial colonies could grow on your petri dish when you intended to isolate only one. Additionally, it is important to protect the people working in the laboratory from infection with the microbes they are handling, and prevent the release of microbes into the environment. The correct application of aseptic techniques prevents these problems from occuring.