Having multiple light sources allows both direct and indirect (reflected) light to highlight architectural features and furnishings. It lets you lead a viewer’s eye where you want it and creates the widest range of effects. The goal will be different for each room or space and different for the time of day or the activity:

• Living rooms are often large enough for lighting “zones” that encourage group conversations, and table lamps help define cozy sub-spaces. Recessed fixtures that highlight artwork, mirrors or window treatments can add another layer that allows for different moods.

• Kitchens need multiple light sources to help prevent shadows, especially in food prep or cleaning zones. Directed task lighting can be used to target countertops or corners, while ceiling pendants provide overall illumination.

• Bathrooms also need shadow-free lighting for personal grooming and for cleaning the space. Wall-mounted fixtures flanking a mirror work better than a single ceiling fixture, and dimming overall light levels can help a master bath take on a spa-like feel.

• Bedrooms need high light levels for such tasks as cleaning or packing, but benefit from bedside lamps for reading and dimmers to create softer moods.

Throughout the book, Martin champions the value of developing a lighting plan early in the building or remodeling process, but she also offers guidance on working with an existing space or home, where the range of options is more limited. Whatever the circumstance, lighting design is a complex art that most building and remodeling guides fail to cover in sufficient detail. Martin’s “bible” is a welcome exception.