diff --git a/src/SandwichClub.Api/GraphQL/SandwichClubMutation.cs b/src/SandwichClub.Api/GraphQL/SandwichClubMutation.cs
index a8b10cd..4d73dbe 100644
--- a/src/SandwichClub.Api/GraphQL/SandwichClubMutation.cs
+++ b/src/SandwichClub.Api/GraphQL/SandwichClubMutation.cs
@@ -7,7 +7,7 @@ namespace SandwichClub.Api.GraphQL
 {
     public class SandwichClubMutation : ObjectGraphType
     {
-        public SandwichClubMutation(IScSession session, IUserService userService, IWeekUserLinkService weekUserLinkService, IWeekService weekService)
+        public SandwichClubMutation(IScSession session, IUserService userService, IWeekService weekService, ITelemetryService telemetryService)
         {
 
             Name = "Mutation";
@@ -24,6 +24,9 @@ public SandwichClubMutation(IScSession session, IUserService userService, IWeekU
                     var weekId = context.GetArgument<int>("weekId");
                     var slices = context.GetArgument<int>("slices");
 
+                    telemetryService.TrackEvent(slices > 0 ? "weekSubscription" : "weekUnsubscription",
+                        new {userId, weekId});
+
                     return await weekService.SubscibeToWeek(weekId, userId, slices);
                 }
             );
diff --git a/src/SandwichClub.Api/Services/ITelemetryService.cs b/src/SandwichClub.Api/Services/ITelemetryService.cs
new file mode 100644
index 0000000..c05c228
--- /dev/null
+++ b/src/SandwichClub.Api/Services/ITelemetryService.cs
@@ -0,0 +1,7 @@
+namespace SandwichClub.Api.Services
+{
+    public interface ITelemetryService
+    {
+        void TrackEvent(string eventName, object customProperties);
+    }
+}
\ No newline at end of file
diff --git a/src/SandwichClub.Api/Services/TelemetryService.cs b/src/SandwichClub.Api/Services/TelemetryService.cs
new file mode 100644
index 0000000..a2750ee
--- /dev/null
+++ b/src/SandwichClub.Api/Services/TelemetryService.cs
@@ -0,0 +1,18 @@
+using System.Linq;
+using Microsoft.ApplicationInsights;
+
+namespace SandwichClub.Api.Services
+{
+    public class TelemetryService : ITelemetryService
+    {
+        private readonly TelemetryClient _client = new TelemetryClient();
+
+        public void TrackEvent(string eventName, object customProperties)
+        {
+            var propertyDictionary = customProperties.GetType().GetFields()
+                .ToDictionary(f => f.Name, f => f.GetValue(customProperties)?.ToString());
+
+            _client.TrackEvent(eventName, propertyDictionary);
+        }
+    }
+}
diff --git a/src/SandwichClub.Api/Services/WeekService.cs b/src/SandwichClub.Api/Services/WeekService.cs
index 1f1f856..9940e60 100644
--- a/src/SandwichClub.Api/Services/WeekService.cs
+++ b/src/SandwichClub.Api/Services/WeekService.cs
@@ -10,10 +10,14 @@ namespace SandwichClub.Api.Services
     public class WeekService : SaveOnlyBaseService<int, Week, IWeekRepository>, IWeekService
     {
         private readonly IWeekUserLinkService _weekUserLinkService;
+        private readonly IUserService _userService;
+        private readonly ITelemetryService _telemetryService;
 
-        public WeekService(IWeekRepository weekRepository, ILogger<WeekService> logger, IWeekUserLinkService weekUserLinkService) : base(weekRepository, logger)
+        public WeekService(IWeekRepository weekRepository, ILogger<WeekService> logger, IWeekUserLinkService weekUserLinkService, ITelemetryService telemetryService, IUserService userService) : base(weekRepository, logger)
         {
             _weekUserLinkService = weekUserLinkService;
+            _telemetryService = telemetryService;
+            _userService = userService;
         }
 
         /// <summary>
@@ -68,6 +72,7 @@ public async Task<IEnumerable<WeekUserLink>> MarkAllLinksAsPaidForUserAsync(int
 
             var currentWeekId = GetWeekId(DateTime.Now);
 
+            var remainingOwed = amountOwed;
             foreach (var week in unpaidWeeks)
             {
                 if (week.WeekId >= currentWeekId)
@@ -76,23 +81,34 @@ public async Task<IEnumerable<WeekUserLink>> MarkAllLinksAsPaidForUserAsync(int
                 // Get the $$$
                 var amountToPay = await GetAmountToPayPerPersonAsync(week.WeekId);
                 // Make sure we don't overpay
-                if (amountOwed - amountToPay <= 0)
+                if (remainingOwed - amountToPay <= 0)
                 {
-                    amountToPay = amountOwed;
-                    amountOwed = 0;
+                    amountToPay = remainingOwed;
+                    remainingOwed = 0;
                 }
                 else
                 {
-                    amountOwed -= amountToPay;
+                    remainingOwed -= amountToPay;
                 }
                 week.Paid = (double) amountToPay;
                 // Do it
                 await _weekUserLinkService.SaveAsync(week);
 
-                if (amountOwed <= 0)
+                if (remainingOwed <= 0)
                     break;
             }
 
+            var user = await _userService.GetByIdAsync(userId);
+            _telemetryService.TrackEvent("Payment",
+                new
+                {
+                    username = $"{user.FirstName} {user.LastName}",
+                    totalAmountToBePaid,
+                    totalAmountPaid,
+                    amountOwed,
+                    remainingOwed
+                });
+
             return unpaidWeeks;
         }
 
diff --git a/test/SandwichClub.Api.Tests/Services/WeekServiceTests.cs b/test/SandwichClub.Api.Tests/Services/WeekServiceTests.cs
index 379a08c..74888f8 100644
--- a/test/SandwichClub.Api.Tests/Services/WeekServiceTests.cs
+++ b/test/SandwichClub.Api.Tests/Services/WeekServiceTests.cs
@@ -33,6 +33,10 @@ public PaymentWeekServiceTests()
                     .Returns((int id, bool ignore) => Task.FromResult(_weekLinks.Where(_ => _.UserId == id)));
                 Mock<IWeekUserLinkService>().Setup(i => i.CountForWeekAsync(It.IsAny<int>()))
                     .Returns((int id) => Task.FromResult(_weekLinks.Count(_ => _.WeekId == id)));
+
+                Mock<IUserService>().Setup(i => i.GetByIdAsync(It.IsAny<int>()))
+                    .Returns((int id) => Task.FromResult(new User {UserId = id}));
+                Mock<ITelemetryService>().Setup(i => i.TrackEvent(It.IsAny<string>(), It.IsAny<object>()));
             }
 
 			internal void AddWeekLinks(int number)