AbstractThis study examines the acquisition of the Spanish spirantization of /b/, /d/ and /g/ by a group of very advanced L2 learners who immigrated to Spain from the United States and have lived in central Spain for many years. While spirantization has received considerable attention in previous L2 research on Spanish, the participants in previous studies have typically been newer learners of Spanish, typically studying at the university level. By examining the production of immigrants to Spain, the present study provides insight into ultimate attainment, and whether this results in a native-like pronunciation in the case of spirantization. Productions are examined both categorically to determine the manner of articulation employed (i.e., approximant, fricative, stop) and also gradiently, using intensity measurements to determine the degree of spirantization when approximants are produced. The comparisons for manner of articulation show significant differences between native Spanish speakers and L2 learners, although when approximants are produced the intensity measurements often do not differ significantly between the two groups. The degree to which individual learners approach native-like pronunciation, both in terms of manner of articulation and intensity measurements of produced approximants, varies considerably.