I want to use different size labels within a single layer. How can I do this?

You can create separate labels for features by defining label classes. Criteria can be set for each class using an SQL query. Under the Layer Properties > select the Labels tab. Change the method of labeling from ‘Label all features the same way’ to ‘Define classes of feature and label each class differently’. This activates additional options in the dialog.

You must create a class for each different label by first adding a new class with the Add button. The user creates a name for each class. After the class name is assigned, use the ‘SQL Query’ button to define the specific criteria for the class. (This SQL Query dialog works the same as all other query dialogs within ArcMap.)

There will be a class designated as ‘Default’, which you may want to turn off by un-checking the box ‘Label features in this class’ to avoid multiple labels for each feature.

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