An endoscope (100) having a multiple diameter working section (104) is disclosed. The endoscope includes a housing (102), a working section, and a rod-lens optical system (514a-d). The housing is at a proximal end of the endoscope. The working section is integral with and extends from the housing. The working section includes at least a first section and a second section. The first section is contiguous to the housing, and the second section is at a distal end of the endoscope. The rod-lens optical system is positioned at least partially in the first section of the working section and at least partially in the second section of the working section. The endoscope is defined such that the outer diameter of the first section is larger than the outer diameter of the second section.
