Auditory perceptual and orthographic confusions challenge foreign language (FL) learners. Hearing first-language (L1) learners establish reliable acoustic parameters for sound categories during infancy (Strange, 2011;Werker & Tees, 1984), before learning how to encode them orthographically. In contrast, FL classrooms simultaneously expose adult learners to new second language (L2) sounds and new orthography, a process which is fundamentally different from L1 alphabetic literacy. Even if both employ the "same" script (e.g., Roman alphabet), grapheme-phoneme correspondences (GPCs) are not congruent between languages, and languages differ in internal consistency of GPCs. Perceptual categories for FL are not robust, requiring greater attentional resources to distinguish L2 phonetic contrasts (Strange, 2011), and likely influenced by the L1, and learners' GPCs are influenced by the L1 (or prior L2s), especially when languages share a script (e.g., German, English). Interaction between orthography and acquisition of L2 sound categories is widely acknowledged, yet poorly understood. We review L2 segment perception research, alphabetic literacy, and early-stage FL instruction, then present results from a longitudinal study of 19 adult FL students beginning to learn German. Prior to instruction, participants spelled 92 auditorily-presented German words featuring 19 phones (9 consonants, 10 vowels). After one semester, they spelled 92 words from course vocabulary lists and 92 unfamiliar words with the same GPCs. We analyze spelling responses to characterize GPC development in FL and generalizability of early gains to novel words.