A good lightning protection system has to start with proper grounding and bonding. If this primary and critical part is not included and done correctly in the equation, nothing else will work. By code all grounding systems must have at least two methods of grounding.
One, of course, is the main service ground (National Electric Code, or NEC 250.52, Grounding Electrode); this is usually an 8- to 10-foot long, ½-inch diameter ground rod. The NEC also requires that a supplementary grounding electrode be installed (250.53 A. 2). Local codes may differ and should always be checked before installing a ground rod system. A grounding electrode conductor sized according to table 250.66 of the NEC is required; this is typically a #4 bare copper conductor. This is the essential start of a good lightning protection system. However this alone may not protect the consumer from surges that come from the exterior of the structure.