Develop a routine. Creating goodbye and hello rituals will help make these transitions more predictable and less stressful for your baby. Before you dash out of the house for work or drop her off at daycare, have a special routine that you follow each morning -- for example, reading a book or eating breakfast together. When you get home, don't immediately head into the kitchen to start dinner after a quick kiss. Instead, take a few minutes to play and give her your undivided attention.
Find a surrogate. A transitional object makes a good fill-in for mom when you're away. Encourage your baby to take a blankie or stuffed animal that feels and smells like home with her to daycare. Or if she's at home, let her hold on to one of your sweaters or jackets. This will help her feel comforted and safe. If she needs the blankie to fall asleep, as a SIDS precaution, have it removed from her crib once she's dozed off.
Examine your childcare. If your baby greets you with desperate tears on a regular basis, check that your daycare provider is nurturing enough for her needs. But if all is well with the caregiver, console yourself that your baby is probably fine all day after her tears dry up.