Hi sharath7, It seems that when you select C,N value from the parameter drop down list, the parameter only return two parameter values, when you use Parameters!Region.Value(2) in your IIF function, it would return a error. More important thing is that the IIF funciton would do precheck with replace the parameter expression with actual value, and then proccess the expression and return value, so the parameter value index refferred in the IIF funciton can’t over the length of the parameter values the user actual selected. Thanks, Bill LuBill Lu TechNet Community Support

Hi when i used the below expression it is working fine for C,N,S but isn't working for C,N why? instead it is throwing as error =IIF(Parameters!Region.Value(0)="C" and Parameters!Region.Value(1)="N" and Parameters!Region.Value(2)="S","XYZ",IIF(Parameters!Region.Value(0)="C" and Parameters!Region.Value(1)="N","YZ",""))

Hi sharath7, It seems that when you select C,N value from the parameter drop down list, the parameter only return two parameter values, when you use Parameters!Region.Value(2) in your IIF function, it would return a error. More important thing is that the IIF funciton would do precheck with replace the parameter expression with actual value, and then proccess the expression and return value, so the parameter value index refferred in the IIF funciton can’t over the length of the parameter values the user actual selected. Thanks, Bill LuBill Lu TechNet Community Support

Sharath, Please make use of SSRS JOIN function, which create delimited string of you multivalue parameters. Once you create delimited string your can surely compare your string. Please refer below Expression which does not give me any Error. =IIF(JOIN(Parameters!Region.Value,",")="C,N,S","XYZ",IIF(JOIN(Parameters!Region.Value,",")="C,N","YZ","")) Let me know if you have any queries.Thanks, Sandip Shinde Please remember to mark the replies as answers if they help you and unmark them if they provide no help.