The best treats, of course, are their favorite ones! Aside from that, here are the key criteria for treat selection for our puzzles:- Healthy (single-ingredient, grain free-ideal)- Non-greasy- Non crumbly- Right size for pawing- Pungent & delicious!A few that we've found work very well (no affiliation):Smittens White Fish Cat TreatsJungle Calling Freeze Dried Cat and Dog TreatsLIFE ESSENTIALSBut your typical Greenies or Temptations work well too