Data Imputation dialog
Clicking Analyze > Data Imputation on the menu opens the Data Imputation dialog. In the following screenshot, regression imputation has been selected. This type of imputation creates a single completed dataset. The incomplete dataset (the one that has missing values) is in the file called Grant_x.sav. Clicking the Impute button will create a new "completed" dataset in a file called Grant_x_C.sav. The completed dataset will contain an imputed value for each value that is missing in the original, incomplete, dataset.