Hiding sensitive data in plain text environment

Hiding sensitive data by recognising a starting key in a plain text environment, wherein the starting key indicates to a working system that the text input subsequent to the starting key is to be hidden according to a specified hiding method; receiving subsequent plain text and the working system carrying out the hiding method on the plain text, wherein the input plain text is not displayed in the plain text environment; and recognising an ending key and ending the hiding method and displaying subsequently input plain text in the plain text environment. The starting key and ending key may also be used to indicate to the working system that the data subsequent to the starting key is hidden according to the specified hiding method. The starting key and ending key are the same or different escape characters. This may be used at command line, parameter files, textual editors or for example in the z/OS operating system data set to protect passwords used an encryption key or scrambling to encode text.