Index: src/wp-admin/network/users.php
===================================================================
--- src/wp-admin/network/users.php	(revision 28766)
+++ src/wp-admin/network/users.php	(working copy)
@@ -77,6 +77,9 @@
 		}
 	}
 
+	/** This action is documented in wp-admin/users.php */
+	do_action( 'delete_user_form', $current_user );
+
 	submit_button( __('Confirm Deletion'), 'delete' );
 	?>
 	</form>
Index: src/wp-admin/users.php
===================================================================
--- src/wp-admin/users.php	(revision 28766)
+++ src/wp-admin/users.php	(working copy)
@@ -244,6 +244,16 @@
 		<?php echo '<label for="delete_option1">' . __( 'Attribute all content to:' ) . '</label> ';
 		wp_dropdown_users( array( 'name' => 'reassign_user', 'exclude' => array_diff( $userids, array($current_user->ID) ) ) ); ?></li>
 	</ul></fieldset>
+	<?php
+	/**
+	 * Fires at the end of the delete users form prior to the confirm button.
+	 *
+	 * @since 4.0.0 
+	 *
+	 * @param WP_User $current_user WP_User object for the user being deleted.
+	 */
+	do_action( 'delete_user_form', $current_user );
+	?>
 	<input type="hidden" name="action" value="dodelete" />
 	<?php submit_button( __('Confirm Deletion'), 'secondary' ); ?>
 <?php else : ?>