i am new user to mainframe programming. i have recently gone through JCL. i am little confused for DISP keyword. When i submit a JCL which includes output in a new PS..... for example : when i merge or sort the data in one PS and get the output in the new PS, i need to change the name of the PS, everytime i submit the JCL. is there any part of code that i may not need to rename the output PS i.e everytime i submit a JCL, first it may check for the PS in which i want the output. Incase the PS exist it may delete the same and in case no such PS exists then it may create the new PS for the output.