I use both a bleat call (Primos "The Can") and a grunt call (Primos "Ruberneck"). I'll usually grunt/bleat every 30 minutes or so. I'll also use them if I see a deer and I can't get a good look at it, many times they will come in for a closer look. Last year I took my best deer to date, and the can and grunt call helped me get him. I saw him in a thicket, on an adjoining piece of property, about 150-200 yds away. I bleated and grunted a couple times, and within two minutes he was only 75 yds away, and looking for a fight. I'm a believer, that's for sure.