Correlational design is a study design for examining the relationships between or among two or more variables in a single group, which can occur at several levels. It is a type of non-experimental design that examines the relationship between two or more variables. It should be remembered that the researcher is not testing the cause-and-effect relationship. A correlational research design investigates relationships between variables without the researcher controlling or manipulating any of them. A correlation reflects the strength and/or direction of the relationship between two or more variables. The direction of a correlation can be either positive or negative. Correlational research refers to a non-experimental research method which studies the relationship between two variables with the help of statistical analysis. Correlational research design does not study the effects of extraneous variables on the variables under study. In cases were carrying out experimental research is unethical, correlational research can be used to determine the relationship between 2 variables. Unwanted or extraneous variables can thus be controlled, the variance of specific variables is enhanced and the possibility of error in measurement is minimized. Nursing and medical Researcher need to have an updated knowledge regarding the various sub design under correlational research. This paper will focus on various types of Correlational design available.