More than a celebration of the 50th anniversary of the International Geophysical Year (IGY), the International Heliophysical Year (IHY) planned for 2007 will be a program of coordinated research in the tradition of a long succession of international programs, of which the IGY is arguably the most famous. One might justifiably ask, Yet another coordinated research program? Given all the others, what will IHY have to offer? Will it lead to better science or just more science? To address these and other questions, nearly 60 scientists participated in the U.S. Planning Workshop for the IHY last April at the National Solar Observatory in Sunspot, New Mexico. The workshop, organized into four working groups on the Sun, the heliosphere, magnetospheres and ionospheres, and atmospheres and climate, took up the challenge posed by these critical questions. While IHY was listed as one of several international year programs in a recent Eos article on the eGY (Electronic Geophysical Year), with NASA as its main sponsor, the sponsorship and roles of these programs relative to each other have been evolving. Initial ideas about the IHY were confined to solar-terrestrial physics, which could fit under the umbrella of the ICSU-sponsored International Polar Year (IPY). Strong voices on the workshop's scientific organizing committee, however, argued for a much broader purview of the IHY, out to the frontiers of heliophysical research in the same way that the IGY reached to the frontiers of geophysical research. At the workshop the broader purview was adopted as the starting point. It was agreed that the new word, heliophysical, not to be confused with the more limited heliospherical (meaning primarily solar wind), should not only embrace atmospheric and solar-terrestrial physics but also include studies of other planets, the outer reaches of the heliosphere, and its interaction with the interstellar medium. The IHY can thus establish and foster interdisciplinary ties with astronomy and astrophysics.