Kramer worked as Lieutenant for the United Nations during the 1960s. She greeted Brigadier Alistair Gordon Lethbridge-Stewart and Sally Wright as they landed in New York for their vacation in 1969. After the death of her detective friend, Paul Dawson, she and Lethbridge-Stewart investigated his murder, to find that the Great Intelligence was behind it. She called in the US Army to help, and followed Lethbridge-Stewart's advice to use sea water against the Yeti invading Manhattan.
In January 1970, Lethbridge-Stewart had Sally ask for Kramer's help in giving the Corps clearance to visit Japan to find Owain Vine. After realising that Vine had been kidnapped and taken home, Lethbridge-Stewart no longer needed her help, but passed along his thanks for her efforts.
Some years later, Lethbridge-Stewart approved Kramer's transfer into UNIT, and promoted her to major. Shortly after this she spent some time in New York with Edward and Anne Travers. (PROSE: Night of the Intelligence)
She met the Doctor in his seventh incarnation in an adventure involving saving Washington, D.C. from disappearing up a time rift. She regarded the Seventh Doctor with a degree of distaste due to his scheming nature.
In 1997, Kramer worked with the Eighth Doctor, Sam Jones, and Carolyn McConnell to eradicate a horde of vampires living in San Francisco. Struck by this incarnation's personality, and the sheer differences from his predecessor, Kramer developed a friendship with the Doctor during this adventure. (PROSE: Vampire Science)
In 2002, the Eighth Doctor phoned Kramer asking for help in dealing with the problem San Francisco was having with its ley lines. Kramer didn't think that UNIT would be able to help the Doctor and told him that he would have to fix the issue himself. (PROSE: Unnatural History)