The present invention relates to an information recording device and method, a program storage medium, and a program, wherein updated file system information can be recorded without changing a logical address. As shown to the upper side in FIG. 18, in the event that data has been recorded, upon a file (Files (Stream+DB)) recorded in region B112 being updated, an updated file is recorded at region B112′ as shown at the middle in FIG. 18. In conjunction with this, main FS (FS (Metadata)), inner side volume structure information, and anchor information, which had been recorded in region B111 until this time, is rendered unreadable, and newly-generated file system information (FS (Metadata)), inner side volume structure information, and anchor information, are recorded in region B111′ in an ISA which is an inner side SA region. The present invention can be applied to a Blu-Ray Disc recording/playing device.