diff --git a/AdhanTests/AdhanTests.swift b/AdhanTests/AdhanTests.swift
index c01ad05..82865bc 100644
--- a/AdhanTests/AdhanTests.swift
+++ b/AdhanTests/AdhanTests.swift
@@ -238,6 +238,36 @@ class AdhanTests: XCTestCase {
         XCTAssertEqual(dateFormatter.string(from: p.isha), "5:02 PM")
     }
     
+    func testJafariMethod() {
+        // Values from http://praytimes.org/code/
+        var comps = DateComponents()
+        comps.year = 2017
+        comps.month = 6
+        comps.day = 16
+        let p = PrayerTimes(coordinates: Coordinates(latitude: 43, longitude: -80), date: comps, calculationParameters: CalculationMethod.shia.params)!
+        
+        let dateFormatter = DateFormatter()
+        dateFormatter.timeZone = TimeZone(identifier: "America/New_York")!
+        dateFormatter.dateStyle = .none
+        dateFormatter.timeStyle = .short
+        
+        XCTAssertEqual(dateFormatter.string(from: p.fajr), "3:43 AM")
+        XCTAssertEqual(dateFormatter.string(from: p.sunrise), "5:40 AM")
+        XCTAssertEqual(dateFormatter.string(from: p.dhuhr), "1:21 PM")
+        XCTAssertEqual(dateFormatter.string(from: p.asr), "5:26 PM")
+        XCTAssertEqual(dateFormatter.string(from: p.maghrib), "9:23 PM")
+        XCTAssertEqual(dateFormatter.string(from: p.isha), "10:40 PM")
+        
+        let p2 = PrayerTimes(coordinates: Coordinates(latitude: 43, longitude: -80), date: comps, calculationParameters: CalculationMethod.tehran.params)!
+        
+        XCTAssertEqual(dateFormatter.string(from: p2.fajr), "3:25 AM")
+        XCTAssertEqual(dateFormatter.string(from: p2.sunrise), "5:40 AM")
+        XCTAssertEqual(dateFormatter.string(from: p2.dhuhr), "1:21 PM")
+        XCTAssertEqual(dateFormatter.string(from: p2.asr), "5:26 PM")
+        XCTAssertEqual(dateFormatter.string(from: p2.maghrib), "9:26 PM")
+        XCTAssertEqual(dateFormatter.string(from: p2.isha), "10:40 PM")
+    }
+    
     func testTimeForPrayer() {
         var comps = DateComponents()
         comps.year = 2016
diff --git a/Sources/Models/CalculationMethod.swift b/Sources/Models/CalculationMethod.swift
index c94d02b..f7b25f3 100644
--- a/Sources/Models/CalculationMethod.swift
+++ b/Sources/Models/CalculationMethod.swift
@@ -57,6 +57,12 @@ public enum CalculationMethod: CaseIterable {
 
     // Singapore
     case singapore
+    
+    // Institute of Geophysics, University of Tehran
+    case tehran
+    
+    // Shia Ithna-Ashari, Leva Institute, Qum
+    case shia
 
     // Other
     case other
@@ -97,6 +103,10 @@ public enum CalculationMethod: CaseIterable {
             var params = CalculationParameters(fajrAngle: 20, ishaAngle: 18, method: self)
             params.methodAdjustments = PrayerAdjustments(dhuhr: 1)
             return params
+        case .tehran:
+            return CalculationParameters(fajrAngle: 17.7, maghribAngle: 4.5, ishaAngle: 14, method: self)
+        case .shia:
+            return CalculationParameters(fajrAngle: 16, maghribAngle: 4, ishaAngle: 14, method: self)
         case .other:
             return CalculationParameters(fajrAngle: 0, ishaAngle: 0, method: self)
         }
diff --git a/Sources/Models/CalculationParameters.swift b/Sources/Models/CalculationParameters.swift
index b7cd158..6ea170a 100644
--- a/Sources/Models/CalculationParameters.swift
+++ b/Sources/Models/CalculationParameters.swift
@@ -29,6 +29,7 @@ import Foundation
 public struct CalculationParameters {
     public var method: CalculationMethod = .other
     public var fajrAngle: Double
+    public var maghribAngle: Double = 0
     public var ishaAngle: Double
     public var ishaInterval: Minute = 0
     public var madhab: Madhab = .shafi
@@ -55,6 +56,11 @@ public struct CalculationParameters {
         self.init(fajrAngle: fajrAngle, ishaInterval: ishaInterval)
         self.method = method
     }
+    
+    init(fajrAngle: Double, maghribAngle: Double, ishaAngle: Double, method: CalculationMethod) {
+        self.init(fajrAngle: fajrAngle, ishaAngle: ishaAngle, method: method)
+        self.maghribAngle = maghribAngle
+    }
 
     func nightPortions() -> (fajr: Double, isha: Double) {
         switch self.highLatitudeRule {
diff --git a/Sources/Models/Madhab.swift b/Sources/Models/Madhab.swift
index 56e6814..0ea22ca 100644
--- a/Sources/Models/Madhab.swift
+++ b/Sources/Models/Madhab.swift
@@ -29,6 +29,7 @@ import Foundation
 public enum Madhab {
     case shafi
     case hanafi
+    case jafari
 
     var shadowLength: Double {
         switch(self) {
@@ -36,6 +37,8 @@ public enum Madhab {
             return 1
         case .hanafi:
             return 2
+        case .jafari:
+            return 1
         }
     }
 }
diff --git a/Sources/PrayerTimes.swift b/Sources/PrayerTimes.swift
index 2cc5b56..df87e96 100644
--- a/Sources/PrayerTimes.swift
+++ b/Sources/PrayerTimes.swift
@@ -46,6 +46,7 @@ public struct PrayerTimes {
         var tempSunrise: Date? = nil
         var tempDhuhr: Date? = nil
         var tempAsr: Date? = nil
+        var tempSunset: Date? = nil
         var tempMaghrib: Date? = nil
         var tempIsha: Date? = nil
         let cal: Calendar = .gregorianUTC
@@ -73,7 +74,7 @@ public struct PrayerTimes {
         }
 
         tempSunrise = cal.date(from: solarTime.sunrise)
-        tempMaghrib = cal.date(from: solarTime.sunset)
+        tempSunset = cal.date(from: solarTime.sunset)
         tempDhuhr = cal.date(from: solarTime.transit)
 
         if let asrComponents = solarTime.afternoon(shadowLength: calculationParameters.madhab.shadowLength) {
@@ -110,7 +111,7 @@ public struct PrayerTimes {
 
         // Isha calculation with check against safe value
         if calculationParameters.ishaInterval > 0 {
-            tempIsha = tempMaghrib?.addingTimeInterval(calculationParameters.ishaInterval.timeInterval)
+            tempIsha = tempSunset?.addingTimeInterval(calculationParameters.ishaInterval.timeInterval)
         } else {
             if let ishaComponents = solarTime.timeForSolarAngle(Angle(-calculationParameters.ishaAngle), afterTransit: true) {
                 tempIsha = cal.date(from: ishaComponents)
@@ -137,6 +138,25 @@ public struct PrayerTimes {
                 tempIsha = safeIsha
             }
         }
+        
+        // Maghrib calculation with check against safe value
+        if calculationParameters.maghribAngle > 0 {
+            if let maghribComponents = solarTime.timeForSolarAngle(Angle(-calculationParameters.maghribAngle), afterTransit: true) {
+                tempMaghrib = cal.date(from: maghribComponents)
+            }
+            
+            if let tempAsr = tempAsr, let tempIsha = tempIsha {
+                // maghrib safe if falls between asr and maghrib
+                if tempMaghrib == nil || tempMaghrib?.compare(tempAsr) == .orderedAscending || tempMaghrib?.compare(tempIsha) == .orderedDescending {
+                    tempMaghrib = tempSunset
+                }
+            } else {
+                // fallback to regular sunset
+                tempMaghrib = tempSunset
+            }
+        } else {
+            tempMaghrib = tempSunset
+        }
 
         // if we don't have all prayer times then initialization failed
         guard let fajr = tempFajr,