There are several reasons why someone could be required to apply for a waiver of inadmissibility to enter the United States. My application was the result of prior criminal convictions but other possible waiver applications include: Waivers of Inadmissibility on Health-Related Grounds (aliens who carry communicable diseases of significant public interest, this could include being HIV positive) Waivers of Inadmissibility due to Fraudulent Misrepresentation (an alien who fraudulently procured a visa and exclusion would result in extreme hardship to a US citizen, spouse or parent of such alien) Waivers of Inadmissibility due to lack of Proper Documentation, including valid passport, visa or border crossing identification (this waiver can be produced for an alien who does not possess a valid passport, visa or other border crossing identification) Waivers of Removability for Unauthorized Work (The section supporting this waiver forgives violations such as acceptance of unauthorized empl...