The optional randomized response technique (ORT) is used when most respondents feel that the subject of the inquiry is sensitive. Still, a minority feels that the inquiry is not sensitive enough and wishes to provide a direct response (DR). A randomized response technique that allows respondents to choose one of the two options: to use RR or DR for providing their responses. ORTs are classified into three categories: full, partial, and mixed. Estimators of population characteristics, their variances, and unbiased estimators of the variances are proposed for the various ORTs under different sampling designs and assumptions. Comparisons of the different types of ORTs are also provided.