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We used those poison pellets (good for mice and rats) in the little dishes. Assuming you don't have other pets or kids to worry about getting into the little dishes, I can honestly say they work wonders. They apparently make the animals thirsty, so they end up heading outside for a water source, and then pass away out there.
At our old house, we had mice that showed up in the kitchen (as Godoggo mentioned, it was due to half-opened boxes of crackers, etc., in the pantry). Put a little tray of those pellets right near the pantry door, and within a day or so, no more mice or droppings.
So, because we didn't have little kids or loose pets, we made sure to have those little trays of pellets also in the basement (where they were likely getting in). If we saw that the pellets had been disturbed or eaten at all, we knew mice had come in. But within a day or so again, the pellets would stay as they were.
When we moved here, we put those trays down in the basement and up on the third floor/attic area right away, not knowing the issues this old Victorian house would have. We've never seen any of the pellets disturbed, never seen evidence of a mouse or other critter anywhere (well, except for the two BATS that showed up that first summer, but we managed to coax them out the front door)... so I've decided I like those pellets as a preventative measure.