To accomplish the study's aims the investigators propose a three phase study: PHASE 1) Formative phase (n=40) to pretest text messages and to explore barriers to cessation and adherence to cessation medication; PHASE 2) a Pretest phase (n=10) to test and revise the intervention components and to assess design issues that may emerge, including those associated with contacting subjects via cell phone, participant capacity to view text messages, timing and content of text messaging, and use of the eCAPs system; and PHASE 3) a Pilot randomized control trial (RCT) in which the investigators will randomize 190 participants, recruited at St. Luke's Roosevelt Comprehensive Care Clinics, to a three-arm study that compares: 1) Standard care (SC), which includes receiving varenicline and brief counseling; 2) SC + daily text messages medication reminders (TxT); or 3) SC + TxT + seven sessions of cell-phone-delivered, adherence-focused behavioral therapy (ABT). Text messages will include medication reminders and motivational messages related to adherence and maintaining abstinence. Participants in all three arms will receive varenicline for 12 weeks. To have a total sample of 150 subjects through the end of treatment at 12 weeks, or 50 subjects in each arm, the investigators will randomize 190 patients to account for a 20% attrition rate. Subjects will be surveyed at six time points including the baseline assessment.

PHASE 1: FORMATIVE EVALUATION Focus groups with patients. Focus groups (lasting from 60 to 90 minutes) will be conducted with HIV+ smokers. To recruit patients for Phase 1, research assistants will approach all individuals within the clinic setting to screen for tobacco use. If they are a current smoker they will be asked if they wish to participate in a scheduled focus group at a convenient time. The research assistants will recruit 80 patients and expect to complete 4 focus groups with 10 participants in each for a total of 40 participants. The main aims of these focus groups are: 1) to obtain feedback on the text message library to determine which messages will be most acceptable and useful, and how often the patients would like to receive messages; 2) to assess comfort with using the pre-paid phone to receive and send messages; 3) to assess confidentiality concerns regarding receiving the text messages and how the patients may be edited to avoid loss of confidentiality; and 4) to explore attitudes and beliefs about varenicline, previous experiences using varenicline, potential challenges with adhering to varenicline, and similarly to explore experiences with past quit attempts and barriers (individual, social, structural) to quitting.

The focus groups will follow written guides. In addition to pre-specified domains drawn from the research questions above, the group facilitator will also listen for and explore emergent topics. Focus groups will be audio-recorded and two research assistants will take notes during each group discussion. All audio recordings will be transcribed verbatim, and transcripts will be supplemented with notes taken during the focus group to ensure accuracy. These transcripts will be analyzed for both pre-determined and emergent themes.

PHASE 2: PRE TEST Prior to starting the RCT the investigators will pre-test the intervention components (ARM 3) to assess study design issues that may emerge, including those associated with contacting subjects via cell phone, participant capacity to view text messages, timing and content of text messaging, and use of the eCAPs system. Ten patients will be enrolled for this phase with a target sample of 6 at end-of-treatment. Quantitative data collection, described below, will follow. The investigators will also conduct post-intervention in-depth interviews with all enrolled subjects to obtain feedback on the components' utility, acceptability, and safety. The research team and consultants will meet after this pilot test to make adjustments to the intervention components prior to the RCT.

PHASE 3: PILOT RCT Overview. This phase of research will compare three smoking cessation interventions that were tested and refined in Phases 1 and 2. A total of 190 PLWHA who are patients at CCC will be screened for this phase with a target sample of 150 at end-of-treatment. The investigators will use a randomized controlled trial design. This is not a formal efficacy trial but a test of the interventions feasibility, safety, and acceptability. Additionally the study will provide preliminary evidence of efficacy of the intervention components with respect to the study's main endpoints: a) adherence to varenicline and b) smoking abstinence at 12 and 24 weeks. This data will inform the design of a larger R01.

Intervention conditions ARM 1: Standard Care (SC). All CCC patients are screened for tobacco use during their routine visits and offered a referral to the New York State (NYS) Quitline. As part of current standard care, all trial participants will receive a self-help information sheet, tailored to HIV+ smokers with frequently asked questions about using varenicline, and a wallet card with the State Quitline number. All subjects will be offered varenicline for 12 weeks. All study participants will be asked whether they prefer to receive phone calls and text messages from the study staff via their own phone or a phone provided by the study, at no cost to the participant. If they choose the latter option, they will be given a pre-paid cell phone for 3 months. Subjects in the SC arm will receive phones to facilitate their ability to call the Quitline for assistance and to enable us to send follow-up appointment reminders via text message. Each pre-paid phone will have an allowance of 200 minutes and unlimited text messages per month. The investigators will instruct participants to use their minutes only toward tobacco treatment or study related purposes. The investigators will track minutes used and if minutes are used out, the investigators will add just enough minutes when they need to contact the subject.

Varenicline therapy: All patients enrolled in the study will be given a 12-week supply of varenicline. The dose will be 0.5 mg/day for 3 days followed by 0.5 mg BID for the next 4 days, and 1 mg BID after first 7 days. The research assistant will explain the use of the medication, review potential side effects, and provide each subject with a wallet size instruction card that will have the dosing schedule and information on how to use the medication. Subjects will receive the medication at a follow-up study visit one week after they are consented. Subjects will receive a three-week supply of varenicline and return at week 4 of the study (timed from the first week they receive the medication). At the week 4 visit they will receive another 4 weeks of medication and will be asked to return at week 8 to receive the final 4 weeks of medication. More than one eCAP bottle will be distributed, depending on the dose of medication and the week of treatment.

ARM 2: SC + Text messages (TxT). Subjects randomized to this arm will receive SC plus twice daily text messaging to remind them to take their medication. Participants will begin receiving text messages the day before they start taking medication, and text messaging will continue for 12 weeks. The text messages are designed to convey relevant information to the subjects while permitting a protective ambiguity. For example, none of the messages transmitted to participants will use the terms HIV or AIDS. In addition, each text message will have the tag "ACT" (Adherence to Cessation Treatment) indicating that it is coming from the study. Participants will receive one medication adherence reminder message and one motivational message regarding tobacco cessation each day. RTI staff will monitor the delivery of the text messages. If participants do not receive text messages for two consecutive days, the study research assistant will call them to assess reasons for message failure. During the study, participants may opt out of receiving any category of messages by contacting the study research assistants and informing him/her of their request. Requests to decline a specific message type or to fully withdraw from the study will be handled promptly and subjects will stop receiving messages within 48 hours of submitting their request to the study research assistant. The investigators will use both symbols and text to accommodate low literacy levels.

ARM 3: SC + TxT + adherence-focused motivational and behavioral therapy (ABT). In addition to SC and TxT, the behavioral intervention group will receive seven proactive cell-phone-delivered counseling sessions over a 6-week period. Drs. Shelley and Krebs have adapted the telephone counseling manual that was developed and tested by Dr. Sherman which was based on Dr. David Kalman's "Treatment Manual for Extended Counseling to Treat Tobacco Addiction,". The draft manual will be reviewed by Drs. Sherman, Wolfe, and Morgenstern and then revised prior to the Phase 2 pretest. The research team will meet again to further revise the manual based on findings from the Phase 2 post-intervention qualitative interviews. The content of the manual combines the principles of Cognitive Behavioral Therapy (CBT) with Motivational Interviewing (MI) techniques, both of which have been applied to smoking cessation with promising results.