'What you see is what you get' is probably the best description. Inspired, plain and clear. With plenty of room for creativity and input from others, but with a clear vision on what should be achieved at the end of the day.
At the same time giving room and respect for other people's expertise. I think the atmosphere during production is one of the most important things to get good results, meaning:
No stress on set, no matter what.
Worked with (among others): Danny Glover, Paul Bazely, Jeroen Krabbé, Derek de Lint, Jeroen Willems, Doña Croll, Aden Gillett.