Prior to coming to Kean, Joiner performed post-doctoral work as a staff scientist with the Shodor Education Foundation, in Durham, NC. Joiner is a Co-Principal Investigator of the Computational Science Education Reference Desk, a Pathway component of the National Science Digital Library. Joiner also works in the area of parallel computing education. Originally trained as a physicist with a specialization in computational astrophysics, Joiner's interest in astronomy is in the modeling of the physical and optical properties of the interstellar medium. Joiner completed his doctoral thesis in 1999 in the Department of Physics, Applied Physics, and Astronomy at Rensselaer Polytechnic Institute, in Troy, NY.