2000 Impala V8 intermittent no start

A friend has a '00 Impala with around 160k miles on it, and is experiencing an intermittent no start. All the lights etc. work, but the starter does not engage. The battery/connections seem ok. He sometimes hears some clicking in the dash area, but no always. Any clues. Maybe a faulty solenoid, but has anyone experienced this?

thx

A v8, not in this car, anyway does the dash security lite stay on when this happens?, has any attempt been made to clean and tighten all battery and ground connections?