Programmer - Switching Views in iPhone SDK?

Programmer Question

How come this won't switch views for me? When I click the button it does nothing...

-(IBAction)howtoplayButtonClicked{
    howToPlayViewController = [[HowToPlayViewController alloc] initWithNibName:@"HowToPlayViewController" bundle:nil];
    [self.navigationController pushViewController:howToPlayViewController animated:YES];
    [HowToPlayViewController release];

}

in the .h file I have this...

#import <UIKit/UIKit.h>
#import "HowToPlayViewController.h"

@interface PopToItViewController : UIViewController {

    HowToPlayViewController *howToPlayViewController;

}

-(IBAction)howtoplayButtonClicked;

@end