Antiretroviral Therapy (ART) Has Decreased The Mortality And Morbidity Of HIV/AIDS, And High Adherence To ART (>95%) Is Necessary For A Good Therapeutic Outcome. Non-Adherence Can Lead To Drug-Resistant HIV Caused By Failure To Achieve Maximal Viral Suppression. Little Is Known About Adherence To ART And Its Determinants Among Ethnically Diverse And Economically Disadvantaged Patients. The Purpose Of The Study Was To Identify The Level Of Adherence And Describe Factors That Influence ART Adherence Among Ethnically Diverse And Economically Disadvantaged Patients. This Is With A View To Providing Information That Could Help Health Care Providers Understand Patient Motivations For Discontinuing Their Antiretroviral Treatment And Helping Patients Collaboratively Develop Treatment Regimens That Facilitate Adherence And Optimize The Outcomes Of HIV/AIDS Therapy. A Cross-Sectional Descriptive Survey Was Used. Data Were Collected Among 400 HIV-Infected Patients On ARV Who Received Pretreatment And Ongoing Adherence Counseling And Education Since 2010 Using A Self-Administered Questionnaire. The Data Were Analyzed Using Statistical Package For Social Sciences (SPSS). Findings Showed That The Self-Reported Adherence To The Specific Timing For Taking The Medications (Medication Schedule) Was Significantly Low (8.3%). The Major Factors For Non-Adherence To Medication Reported In This Study Were Being Busy At Work Or School, Forgetfulness, Fasting And Travelling Away From Home. Also, Employment Status Was Associated With Poor Adherence, Which May Be Corroborated By The Major Reason For Non-Adherence (Busy At Work Or School). This Study Is One Of The First Steps In The Exploration Of The Relationship Of Factors Responsible And Medication Adherence Among HIV Patients. This Study Used Three Different Measures Of Medication Adherence. These Are Patients’ Knowledge Of The Benefits Of Taking The Drugs, Adherence To A Medication Schedule, And The Number Of Prescribed Doses Of Medications Missed. Health Care Providers Must Identify Possible Barriers To Adherence At The Earliest And Provide Appropriate Solutions. These Factors Should Be Considered When Designing And Implementing Adherence Interventions.