diff --git a/examples/vpc-transit-gateway-attachment/variables.vpc-transit-gateway.tf b/examples/vpc-transit-gateway-attachment/variables.vpc-transit-gateway.tf
index 7f89608..ef6d8a3 100644
--- a/examples/vpc-transit-gateway-attachment/variables.vpc-transit-gateway.tf
+++ b/examples/vpc-transit-gateway-attachment/variables.vpc-transit-gateway.tf
@@ -1,3 +1,96 @@
+variable "tgw_environment" {
+  description = "Transit Gateway environment route table (services, dev, test, stage, prod, cre)"
+  type        = string
+  default     = null
+
+  validation {
+    condition     = contains(["services", "dev", "test", "stage", "prod", "cre"], var.tgw_environment)
+    error_message = "The tgw_environment must contain one of the legal values: services, dev, test, stage, prod, cre"
+  }
+}
+
+variable "tgw_environment_exists" {
+  description = "Transit Gateway environment already setup in another VPC (say, for multiple test enviroments but diff vpc like test,ite,qa)"
+  type        = bool
+  default     = false
+}
+
+# example: site=hq, environment=services, sequence=1, bgp_asn_id=asn, ip_address=endpoint-ip-on-prem, tunnel_ips=169.254.x.1/30,169.254.x.2/30, preshared_keys=bob,alice
+variable "tgw_vpn_settings" {
+  description = "Transit Gateway VPN Connection details array of objects"
+  type = list(object(
+    {
+      site        = string
+      environment = string
+      sequence    = number
+      #      region         = optional(string)
+      region            = string
+      bgp_asn_id        = number
+      ip_address        = string
+      tunnel_ips        = list(string)
+      preshared_keys    = list(string)
+      tunnel_interfaces = optional(list(number), [0, 0])
+      tunnel_track      = optional(list(number), [0, 0])
+      tunnel_loopback   = optional(number, 0)
+      #      tunnel_interfaces = optional(list(number))
+      #      tunnel_track      = optional(list(number))
+      #      tunnel_loopback   = optional(number)
+    }
+  ))
+  default = []
+}
+
+variable "tgw_routing_prefix_list" {
+  description = "Managed prefix list for TGW routing"
+  type        = string
+  default     = ""
+}
+
+variable "tgw_vpn_routing_prefix_list" {
+  description = "Managed prefix list for TGW VPN routing"
+  type        = string
+  default     = ""
+}
+
+variable "tgw_enable_vpn" {
+  description = "Enable AWS VPN Configuration on the Transit Gateway (default: false)"
+  type        = bool
+  default     = false
+}
+
+variable "tgw_routing_cidr_blocks" {
+  description = "List of CIDR blocks for which TGW routing will apply.  This would include all of the AWS CIDR blocks, possibly only a 0.0.0.0/0 route, but not any on-prem routes"
+  type        = list(string)
+  default     = []
+}
+
+variable "tgw_vpn_routing_cidr_blocks" {
+  description = "List of CIDR blocks for which TGW routing will apply for the VPN learned blocks, specifically on-prem routes. This may be replaced by a 0/0 route in the future"
+  type        = list(string)
+  default     = []
+}
+
+## # to use the optional(), you have to enable experiments. Probably do not need this at this time
+## # see the docs: https://www.terraform.io/language/expressions/type-constraints
+## 
+## terraform {
+##   experiments = [module_variable_optional_attrs]
+## }
+## 
+
+
+variable "generate_yaml_files" {
+  description = "Flag to enable or disable generation of YAML file from VPN information"
+  type        = bool
+  default     = true
+}
+
+variable "use_single_cgw" {
+  description = "Flag to enable or disable the use of a single customer gateway per site vs one per site and VPN"
+  type        = bool
+  default     = false
+}
+
 variable "network_account_profile" {
   description = "AWS profile of the source account sharing the VPC resources"
   type        = string