Familiar Concentration
(Lost Empires of Faerun, page 8, DnD 3.5)
[General]
In the tradition of Narfell's ancient summoners, your familiar can concentrate to maintain spells for you.
Prerequisite
Improved Familiar, caster level 9th
Benefit
When you cast a spell requiring concentration, you can designate your familiar as the "concentrator." At any time during the spell's duration, you can hand over control of it to your familiar as a free action, provided the creature is within 5 feet of you and its Intelligence score is at least 10 + the level of the spell. The familiar then concentrates to maintain and direct the spell just as you would. You cannot take back control of a spell once you have transferred it to your familiar.