diff --git a/src/Discord.Net.Core/Entities/Interactions/ApplicationCommandOptionType.cs b/src/Discord.Net.Core/Entities/Interactions/ApplicationCommandOptionType.cs
index 0f919f1f6..5bb00797b 100644
--- a/src/Discord.Net.Core/Entities/Interactions/ApplicationCommandOptionType.cs
+++ b/src/Discord.Net.Core/Entities/Interactions/ApplicationCommandOptionType.cs
@@ -53,6 +53,11 @@ namespace Discord
         /// <summary>
         ///     A <see cref="double"/>.
         /// </summary>
-        Number = 10
+        Number = 10,
+
+        /// <summary>
+        ///     A <see cref="Discord.Attachment"/>.
+        /// </summary>
+        Attachment = 11
     }
 }
diff --git a/src/Discord.Net.Interactions/InteractionService.cs b/src/Discord.Net.Interactions/InteractionService.cs
index b394109a5..475622f0b 100644
--- a/src/Discord.Net.Interactions/InteractionService.cs
+++ b/src/Discord.Net.Interactions/InteractionService.cs
@@ -163,6 +163,7 @@ namespace Discord.Interactions
             {
                 [typeof(IChannel)] = typeof(DefaultChannelConverter<>),
                 [typeof(IRole)] = typeof(DefaultRoleConverter<>),
+                [typeof(IAttachment)] = typeof(DefaultAttachmentConverter<>),
                 [typeof(IUser)] = typeof(DefaultUserConverter<>),
                 [typeof(IMentionable)] = typeof(DefaultMentionableConverter<>),
                 [typeof(IConvertible)] = typeof(DefaultValueConverter<>),
diff --git a/src/Discord.Net.Interactions/TypeConverters/DefaultEntityTypeConverter.cs b/src/Discord.Net.Interactions/TypeConverters/DefaultEntityTypeConverter.cs
index 9107fbf35..fb493ed72 100644
--- a/src/Discord.Net.Interactions/TypeConverters/DefaultEntityTypeConverter.cs
+++ b/src/Discord.Net.Interactions/TypeConverters/DefaultEntityTypeConverter.cs
@@ -20,6 +20,11 @@ namespace Discord.Interactions
         }
     }
 
+    internal class DefaultAttachmentConverter<T> : DefaultEntityTypeConverter<T> where T : class, IAttachment
+    {
+        public override ApplicationCommandOptionType GetDiscordType() => ApplicationCommandOptionType.Attachment;
+    }
+
     internal class DefaultRoleConverter<T> : DefaultEntityTypeConverter<T> where T : class, IRole
     {
         public override ApplicationCommandOptionType GetDiscordType ( ) => ApplicationCommandOptionType.Role;
diff --git a/src/Discord.Net.Rest/API/Common/ApplicationCommandInteractionDataResolved.cs b/src/Discord.Net.Rest/API/Common/ApplicationCommandInteractionDataResolved.cs
index 5b4b83e23..690be6cef 100644
--- a/src/Discord.Net.Rest/API/Common/ApplicationCommandInteractionDataResolved.cs
+++ b/src/Discord.Net.Rest/API/Common/ApplicationCommandInteractionDataResolved.cs
@@ -18,5 +18,7 @@ namespace Discord.API
         public Optional<Dictionary<string, Role>> Roles { get; set; }
         [JsonProperty("messages")]
         public Optional<Dictionary<string, Message>> Messages { get; set; }
+        [JsonProperty("attachments")]
+        public Optional<Dictionary<string, Attachment>> Attachments { get; set; }
     }
 }
diff --git a/src/Discord.Net.Rest/Entities/Interactions/CommandBase/RestResolvableData.cs b/src/Discord.Net.Rest/Entities/Interactions/CommandBase/RestResolvableData.cs
index 710207ef9..9353a8530 100644
--- a/src/Discord.Net.Rest/Entities/Interactions/CommandBase/RestResolvableData.cs
+++ b/src/Discord.Net.Rest/Entities/Interactions/CommandBase/RestResolvableData.cs
@@ -19,6 +19,9 @@ namespace Discord.Rest
         internal readonly Dictionary<ulong, RestMessage> Messages
             = new Dictionary<ulong, RestMessage>();
 
+        internal readonly Dictionary<ulong, Attachment> Attachments
+            = new Dictionary<ulong, Attachment>();
+
         internal async Task PopulateAsync(DiscordRestClient discord, RestGuild guild, IRestMessageChannel channel, T model)
         {
             var resolved = model.Resolved.Value;
@@ -91,6 +94,16 @@ namespace Discord.Rest
                     Messages.Add(message.Id, message);
                 }
             }
+            
+            if (resolved.Attachments.IsSpecified)
+            {
+                foreach (var attachment in resolved.Attachments.Value)
+                {
+                    var discordAttachment = Attachment.Create(attachment.Value);
+
+                    Attachments.Add(ulong.Parse(attachment.Key), discordAttachment);
+                }
+            }
         }
     }
 }
diff --git a/src/Discord.Net.Rest/Entities/Interactions/SlashCommands/RestSlashCommandDataOption.cs b/src/Discord.Net.Rest/Entities/Interactions/SlashCommands/RestSlashCommandDataOption.cs
index bb931f68e..cbb958968 100644
--- a/src/Discord.Net.Rest/Entities/Interactions/SlashCommands/RestSlashCommandDataOption.cs
+++ b/src/Discord.Net.Rest/Entities/Interactions/SlashCommands/RestSlashCommandDataOption.cs
@@ -43,6 +43,7 @@ namespace Discord.Rest
                     case ApplicationCommandOptionType.Role:
                     case ApplicationCommandOptionType.Channel:
                     case ApplicationCommandOptionType.Mentionable:
+                    case ApplicationCommandOptionType.Attachment:
                         if (ulong.TryParse($"{model.Value.Value}", out var valueId))
                         {
                             switch (Type)
@@ -80,6 +81,9 @@ namespace Discord.Rest
                                         }
                                     }
                                     break;
+                                case ApplicationCommandOptionType.Attachment:
+                                    Value = data.ResolvableData.Attachments.FirstOrDefault(x => x.Key == valueId).Value;
+                                    break;
                                 default:
                                     Value = model.Value.Value;
                                     break;
diff --git a/src/Discord.Net.WebSocket/Entities/Interaction/SlashCommands/SocketSlashCommandDataOption.cs b/src/Discord.Net.WebSocket/Entities/Interaction/SlashCommands/SocketSlashCommandDataOption.cs
index 265eda75b..2a44b4e03 100644
--- a/src/Discord.Net.WebSocket/Entities/Interaction/SlashCommands/SocketSlashCommandDataOption.cs
+++ b/src/Discord.Net.WebSocket/Entities/Interaction/SlashCommands/SocketSlashCommandDataOption.cs
@@ -39,6 +39,7 @@ namespace Discord.WebSocket
                     case ApplicationCommandOptionType.Role:
                     case ApplicationCommandOptionType.Channel:
                     case ApplicationCommandOptionType.Mentionable:
+                    case ApplicationCommandOptionType.Attachment:
                         if (ulong.TryParse($"{model.Value.Value}", out var valueId))
                         {
                             switch (Type)
@@ -76,6 +77,9 @@ namespace Discord.WebSocket
                                         }
                                     }
                                     break;
+                                case ApplicationCommandOptionType.Attachment:
+                                    Value = data.ResolvableData.Attachments.FirstOrDefault(x => x.Key == valueId).Value;
+                                    break;
                                 default:
                                     Value = model.Value.Value;
                                     break;
diff --git a/src/Discord.Net.WebSocket/Entities/Interaction/SocketBaseCommand/SocketResolvableData.cs b/src/Discord.Net.WebSocket/Entities/Interaction/SocketBaseCommand/SocketResolvableData.cs
index c065637ca..d722c5a13 100644
--- a/src/Discord.Net.WebSocket/Entities/Interaction/SocketBaseCommand/SocketResolvableData.cs
+++ b/src/Discord.Net.WebSocket/Entities/Interaction/SocketBaseCommand/SocketResolvableData.cs
@@ -16,6 +16,9 @@ namespace Discord.WebSocket
         internal readonly Dictionary<ulong, SocketMessage> Messages
             = new Dictionary<ulong, SocketMessage>();
 
+        internal readonly Dictionary<ulong, Attachment> Attachments
+            = new Dictionary<ulong, Attachment>();
+
         internal SocketResolvableData(DiscordSocketClient discord, ulong? guildId, T model)
         {
             var guild = guildId.HasValue ? discord.GetGuild(guildId.Value) : null;
@@ -104,6 +107,16 @@ namespace Discord.WebSocket
                     Messages.Add(message.Id, message);
                 }
             }
+
+            if (resolved.Attachments.IsSpecified)
+            {
+                foreach (var attachment in resolved.Attachments.Value)
+                {
+                    var discordAttachment = Attachment.Create(attachment.Value);
+
+                    Attachments.Add(ulong.Parse(attachment.Key), discordAttachment);
+                }
+            }
         }
     }
 }