The main purpose of this study was to examine the predictive qualities of objective and perceived spiritual and religious compatibility on marital functioning. Objective compatibility compares the extent to which 2 self-reports of the couple agree, and perceived compatibility examines the extent to which a person's perception of his or her spouse agrees with what the spouse reports about him- or herself. These compatibility indices were calculated by using McCrae's (2008) index of profile agreement, which matches up 2 profiles, over a range of elements. This study examined these 2 types of compatibility on spirituality and religiosity as predictors of marital functioning. Additionally, the author created the Spiritual Problems Checklist for Couples (SPCC) for this study to determine whether spiritual and/or religious problems in a marital relationship could predict marital functioning after controlling for the effects of intra- and inter-personal problems. The sample included 101 married, heterosexual couples for a total of 202 participants, ranging in age from 22 to 73 years (M = 35.35). Most of the participants were Catholic (48.7%). The remaining participants were Lutheran (2.5%), Methodist (7%), Episcopal (2.5%), Unitarian (3%), Baptist (3%), Other Christian (18.6%), Jewish (1%), Buddhist (2.5%), Atheist/Agnostic (7.5%), and Other Faith Tradition (3.5%). The measures used in this study were the Assessment of Spirituality and Religious Sentiments (Piedmont, 2010), Joint Religious Activities (Mahoney et al., 1999), Bipolar Adjective Rating Scale (Piedmont, 1999a), Couple Critical Incident Checklist (CCICL, Piedmont & Piedmont, 1996), Marital Adjustment Test (Locke & Wallace, 1959), Personal Assessment of Intimacy in Relationships (Schaefer & Olson, 1981), the SPCC, and a demographic questionnaire. The results show that of the 4 compatibility indices, objective religious compatibility and perceived spiritual compatibility were the significant predictors of marital functioning after controlling for self-rated personality. In addition, the initial construction of the SPCC produced positive findings by predicting marital functioning over and above the effects of the CCICL. This study contributes to the marital research field by (a) showing the value of collected self- and observer ratings, (b) using profile agreement to calculate levels of compatibility (similarity) between husbands and wives, (c) providing an incremental validity model, (d) demonstrating that spiritual and religious compatibility predict marital functioning, and (e) showing that the number of spiritual problems a person is having with his or her spouse is associated with marital functioning.