Parental alienation continues to be a disputed concept among researchers, clinicians and legal experts. I have updated my list of research articles on this topic (2010-2015).
For a thoughtful history of the study and controversies regarding parental alienation see:
Rand, D. C. (2011). Parental alienation critics and the politics of science. American Journal of Family Therapy, 39(1), 48-71. doi:http://dx.doi.org/10.1080/01926187.2010.533085