Over 8000 line positions and intensities of phosphine (PH 3 ) at 3μm have been measured at 0.0115cm −1 resolution with the McMath-Pierce Fourier Transform spectrometer at Kitt Peak. The observed line intensities ranged from 4.13×10 −6 to 4.69×10 −2 cm −2 atm −1 at 296K, for line positions between 2724.477 and 3601.652cm −1 . This region spans eight interacting vibrational states: 3ν 2 (2940.8cm −1 ), 2ν 2 +ν 4 (3085.6cm −1 ), ν 2 +2ν 4 (3214.9cm −1 ), ν 1 +ν 2 (3307.6cm −1 ), ν 2 +ν 3 (3310.5cm −1 ), 3ν 4 (∼3345cm −1 ), ν 1 +ν 4 (3426.9cm −1 ), and ν 3 +ν 4 (3432.9cm −1 ). Assignments have been determined for all the bands except 3ν 4 (a weak band in a highly congested area) for a total of 4232 transitions. The total integrated intensity for this region is 5.70cm −2 atm −1 near 296K, and assigned lines account for 79% of the observed absorption. The two strongest bands in the region are ν 1 +ν 4 and ν 3 +ν 4 with band strengths at 296K of 1.61 and 2.01cm −2 atm −1 , respectively. An empirical database of PH 3 line parameters (positions, intensities, and assignments) is now available. Lower state energies (corresponding to assignments from this study) and line widths from the literature are included; default values are used for unassigned features.