The introduction and spread of "Ms" as the courtesy address title for women is a cornerstone of feminist linguistic planning for English. Its introduction aimed to eradicate the discriminatory inequity in the address system that exposed women through their (non)marital relationship with men. The understanding, use and impact of the courtesy title are fairly well documented, particularly for Englishes of Australia (e.g. Pauwels 1987; 1998; 2001; 2003), US and Britain (Romaine 2001) and New Zealand (Holmes 2001). We have little knowledge of the form's spread, impact and use by speakers for whom English is not the dominant language but forms part of their linguistic repertoire. Graddol (1997) argues that English-speaking bilinguals will outnumber first language speakers and, "increasingly will decide the global future of the language" (p. 10). Such contexts of English--second / third / foreign--usage loosely align with locales Kachru (1997) identified as "expanding circles", and to some extent, many of the "outer circle" Englishes, e.g. Hong Kong. In this paper we take up a new direction in feminist language planning: the exploration of courtesy title use and practices by English-speaking mono-/bi-/multilingual women around the world. We draw upon online survey data (available from http://www.teagirl.arts.uwa.edu.au/) to probe respondents' strategies for addressing unknown women, as well as women's use of courtesy titles for themselves. Our mapping of practices associated with "Ms" reveals an unexpected pattern of diffusion with implications for evaluating planned social language change. In relation to "Ms", the implementation of feminist linguistic policy does not cohere with a pattern of spread from inner to outer to expanding "circles" of English or from "first language speaker" to..."foreign language speaker" diffusion. The locale and personal contexts associated with education, awareness and personal commitment to gender equity interact in complicating and surprising ways. Indeed our research exposes a new directionality for "Ms" as a preferred form for unknown women, without necessarily implicating its use in self-naming for many bilingual women resident in "outer circle" locales. (Contains 7 tables and 3 endnotes. )