  We present sensitive and high resolution 21 cm observations of the dwarf
irregular (dIm) galaxy DDO 43, in conjunction with optical broad and narrow
band images in U, B, V, and Halpha. The observations are used to examine the
relationship between its HI morphology and kinematics to past and present star
formation. Optically, it is a small (R_25 = 990 pc), faint (M_B of -14.0) Im
with a slightly boxy shape. In HI, DDO 43 has an extended (R_HI/R_Ho = 2.8) gas
envelope. There is a high density ridge associated with the optical body of the
galaxy, containing several higher density knots and lower density holes. The
largest hole is ~850x530 pc. No expansion is detected, so it must be relatively
old. The largest and potentially oldest (7-70 Myr) of the six identified star
clusters is located at the western edge of the hole. Four of the other clusters
are located near high density peaks. There are several HII regions, most of
which are associated with peaks in the HI surface density. The overall star
formation rate is average for its type. In many ways, DDO 43 is a very typical
dwarf irregular galaxy. Its HI morphology is consistent with a history of
episodes of localized star ormation that create holes and shells in the ISM,
some of which can overlap. These features are located within the area of
solid-body rotation in the galaxy; the lack of shear in these small systems
allows such structures to persist for long periods of time.
