Spray Dutch oven (or pot) with nonstick cooking spray or oil. Add ground turkey, carrots, onion, celery, garlic, and 1 Tbls of the taco seasoning mix; cook over medium heat for 10-12 minutes or until turkey is no longer pink and vegetables are tender, stirring frequently.
Stir in water or broth, tomatoes, and remaining taco seasoning mix. Bring to a boil. Reduce heat; simmer 20 minutes, stirring occasionally.
Add barley; simmer an additional 15 minutes or until barley is tender.
Stir in oregano and serve with crusty Italian bread.