diff --git a/src/main/kotlin/com/featurevisor/sdk/Instance+Fetch.kt b/src/main/kotlin/com/featurevisor/sdk/Instance+Fetch.kt
index 025fd2c..ea950c8 100644
--- a/src/main/kotlin/com/featurevisor/sdk/Instance+Fetch.kt
+++ b/src/main/kotlin/com/featurevisor/sdk/Instance+Fetch.kt
@@ -56,8 +56,19 @@ private inline fun fetch(
                 }
                 val responseBodyString = responseBody.string()
                 FeaturevisorInstance.companionLogger?.debug(responseBodyString)
-                val content = json.decodeFromString<DatafileContent>(responseBodyString)
-                completion(Result.success(content))
+                try {
+                    val content = json.decodeFromString<DatafileContent>(responseBodyString)
+                    completion(Result.success(content))
+                } catch(throwable: Throwable) {
+                    completion(
+                        Result.failure(
+                            FeaturevisorError.UnparsableJson(
+                                responseBody.string(),
+                                response.message
+                            )
+                        )
+                    )
+                }
             } else {
                 completion(
                     Result.failure(
diff --git a/src/main/kotlin/com/featurevisor/sdk/Instance.kt b/src/main/kotlin/com/featurevisor/sdk/Instance.kt
index 3a7fb14..8dcc271 100644
--- a/src/main/kotlin/com/featurevisor/sdk/Instance.kt
+++ b/src/main/kotlin/com/featurevisor/sdk/Instance.kt
@@ -10,10 +10,7 @@ import com.featurevisor.types.BucketValue
 import com.featurevisor.types.Context
 import com.featurevisor.types.DatafileContent
 import com.featurevisor.types.EventName
-import com.featurevisor.types.EventName.ACTIVATION
-import com.featurevisor.types.EventName.READY
-import com.featurevisor.types.EventName.REFRESH
-import com.featurevisor.types.EventName.UPDATE
+import com.featurevisor.types.EventName.*
 import com.featurevisor.types.Feature
 import com.featurevisor.types.StickyFeatures
 import kotlinx.coroutines.Job
@@ -81,6 +78,11 @@ class FeaturevisorInstance private constructor(options: InstanceOptions) {
                     ACTIVATION, onActivation
                 )
             }
+            if (onError != null) {
+                emitter.addListener(
+                    ERROR, onError
+                )
+            }
 
             on = emitter::addListener
             off = emitter::removeListener
@@ -104,7 +106,7 @@ class FeaturevisorInstance private constructor(options: InstanceOptions) {
                             if (refreshInterval != null) startRefreshing()
                         } else {
                             logger?.error("Failed to fetch datafile: $result")
-                            throw FetchingDataFileFailed(result.toString())
+                            emitter.emit(ERROR)
                         }
                     }
                 }
diff --git a/src/main/kotlin/com/featurevisor/sdk/InstanceOptions.kt b/src/main/kotlin/com/featurevisor/sdk/InstanceOptions.kt
index 86e72bd..48254db 100644
--- a/src/main/kotlin/com/featurevisor/sdk/InstanceOptions.kt
+++ b/src/main/kotlin/com/featurevisor/sdk/InstanceOptions.kt
@@ -20,6 +20,7 @@ data class InstanceOptions(
     val onReady: Listener? = null,
     val onRefresh: Listener? = null,
     val onUpdate: Listener? = null,
+    val onError: Listener? = null,
     val refreshInterval: Long? = null, // seconds
     val stickyFeatures: StickyFeatures? = null,
 ) {
diff --git a/src/main/kotlin/com/featurevisor/types/Types.kt b/src/main/kotlin/com/featurevisor/types/Types.kt
index 703ac0f..862f296 100644
--- a/src/main/kotlin/com/featurevisor/types/Types.kt
+++ b/src/main/kotlin/com/featurevisor/types/Types.kt
@@ -304,6 +304,7 @@ enum class EventName {
     REFRESH,
     UPDATE,
     ACTIVATION,
+    ERROR,
 }
 
 /**