Interrupt you only when it matters
Most calls can wait for a message. Some cannot. You decide which, with rules such as "the caller has water coming through a ceiling" or "an existing client asks for their solicitor on completion day".
Who gets the call
Each rule says who to put the caller through to: you, a colleague or the person on call. She tells the caller she is putting them through first.
Safety first
Industry editions come with safety guidance built in. A caller who smells gas is told to leave the property and call the gas emergency line before anything else, and anyone describing a medical emergency is told to call 999.
Different rules out of hours
Out of hours she can take a message instead of putting calls through, give your next opening time, and still flag anything urgent so you see it first.