A head for an iron-type golf club, comprising: an iron-type face having a ball striking surface configured for striking a ball and a rear surface opposite the ball striking surface; an iron-type body connected to the face, the body comprising a plurality of peripheral walls extending rearward from outer edges of the face, the peripheral walls including a sole member extending rearward from a bottom edge of the face, the sole member having a sole surface configured to confront a playing surface; an elongated channel located in the sole surface of the body adjacent to a bottom edge of the face, the channel being defined by a first end located on the sole surface, a second end located on the sole surface, and two edges (146, 148) extending across the sole surface between the first and second ends, the channel having a length defined between the first and second ends, and the channel comprising a trough that is recessed from the sole surface and two opposed side walls extending from the trough to the edges of the channel, wherein the side walls of the channel are both generally parallel to a plane of the face when viewed in cross-section, and wherein the channel is spaced rearwardly from the bottom edge of the face and the edges of the channel are generally parallel to the bottom edge, and the channel has a depth of recession from the sole surface; and a flexible polymer insert connected to the body and mounted within the channel, wherein the channel is configured to influence an impact of a ball on the face by flexing in response to the impact, such that some of a force of the impact is transferred through the spacing portion to the channel, causing the body to flex at the channel, and wherein the insert is configured to exert additional response force on the face when the channel flexes in response to the impact, characterized in that: the depth of the channel is tapered, such that the depth of the channel is greater at a center of the channel than at opposed ends of the channel. an iron-type face having a ball striking surface configured for striking a ball and a rear surface opposite the ball striking surface; an iron-type body connected to the face, the body comprising a plurality of peripheral walls extending rearward from outer edges of the face, the peripheral walls including a sole member extending rearward from a bottom edge of the face, the sole member having a sole surface configured to confront a playing surface; an elongated channel located in the sole surface of the body adjacent to a bottom edge of the face, the channel being defined by a first end located on the sole surface, a second end located on the sole surface, and two edges (146, 148) extending across the sole surface between the first and second ends, the channel having a length defined between the first and second ends, and the channel comprising a trough that is recessed from the sole surface and two opposed side walls extending from the trough to the edges of the channel, wherein the side walls of the channel are both generally parallel to a plane of the face when viewed in cross-section, and wherein the channel is spaced rearwardly from the bottom edge of the face and the edges of the channel are generally parallel to the bottom edge, and the channel has a depth of recession from the sole surface; and a flexible polymer insert connected to the body and mounted within the channel, wherein the channel is configured to influence an impact of a ball on the face by flexing in response to the impact, such that some of a force of the impact is transferred through the spacing portion to the channel, causing the body to flex at the channel, and wherein the insert is configured to exert additional response force on the face when the channel flexes in response to the impact, characterized in that: the depth of the channel is tapered, such that the depth of the channel is greater at a center of the channel than at opposed ends of the channel.