It used to be called synchro-sunlight – using a flash to put some light into a shadowed area, often a face. Controlling contrast, when there’s cheerful sunlight to give the picture a summery look.
But you can use flash, or a continuous light (the ubiquitous Rotolight will let you match colour temperature, if you’ve got deep pockets and a hankering after perfect colour), or a reflector.
Even a newspaper (pink Financial Times excepted) will do. Sometimes, a location will provide a big light surface.
And these days, digital processing offers a rescue remedy, or five: Nik Color Efex offers a fill option, with controllable direction, brightness and colour, while you can dodge and burn, gently, a little at a time.
Or, simply, turn your subject away from the sunshine, letting the direct light form a halo round him or her, and expose for the shadows.
I’m heading out with my wife and daughter today – maybe a family portrait – if the sun stays out…