diff --git a/datatype.go b/datatype.go
index 687d235..6933880 100644
--- a/datatype.go
+++ b/datatype.go
@@ -22,6 +22,7 @@ type cValue struct {
 	durval  time.Duration
 	boolval bool
 	strval  string
+	mapval  map[string]cValue
 	err     error
 }
 
diff --git a/envconf.go b/envconf.go
index f50fa54..882e879 100644
--- a/envconf.go
+++ b/envconf.go
@@ -18,9 +18,11 @@ type cEntry struct {
 	defval string // The default value
 	hasdef bool   // Default value is defined
 }
+
 type Config struct {
 	parsed bool
 	env    map[string]cEntry
+	mapEnv map[string]map[string]cEntry
 }
 
 // NewConfig returns an envconf.Config that is used to read configuration from environment variables.
@@ -30,10 +32,21 @@ func NewConfig() *Config {
 	config := new(Config)
 	config.parsed = false
 	config.env = make(map[string]cEntry)
+	config.mapEnv = make(map[string]map[string]cEntry)
+
 	for _, v := range os.Environ() {
 		splitted := strings.SplitN(v, "=", 2)
 		if len(splitted) == 2 {
-			key := strings.TrimSpace(strings.ToUpper(splitted[0]))
+			key := cleanKey(splitted[0])
+			keysplit := strings.Split(key, "_")
+			left := ""
+			right := ""
+
+			if len(keysplit) > 1 {
+				left = strings.Join(keysplit[:len(keysplit)-1], "_")
+				right = keysplit[len(keysplit)-1]
+			}
+
 			if unicode.IsLetter(getFirstRune(key)) {
 				var entry cEntry
 				entry.value = splitted[1]
@@ -41,13 +54,14 @@ func NewConfig() *Config {
 				entry.unset = false
 				entry.empty = false
 				config.env[key] = entry
+				config.mapEnv[left][right] = entry
 			}
 		}
 	}
 	return config
 }
 
-// Define defines the type of an environment variable.
+// Define the type of an environment variable.
 // Variables without a defined type will be ignored by Parse.
 func (c *Config) Define(key string, dtype DataType) {
 	upper := strings.ToUpper(key)
@@ -64,7 +78,20 @@ func (c *Config) Define(key string, dtype DataType) {
 	}
 }
 
-// DefineDefault defines the type and default value of an environment variable.
+// Define the type of an environment variable.
+// Variables without a defined type will be ignored by Parse.
+func (c *Config) DefineMap(key string, dtype DataType) {
+	upper := strings.ToUpper(key)
+	entries, ok := c.mapEnv[upper]
+	if ok {
+		for mapKey, entry := range entries {
+			entry.dtype = dtype
+			c.mapEnv[key][mapKey] = entry
+		}
+	}
+}
+
+// Define the type and default value of an environment variable.
 // Variables without a defined type will be ignored by Parse.
 func (c *Config) DefineDefault(key string, val string, dtype DataType) {
 	upper := strings.ToUpper(key)
@@ -108,6 +135,14 @@ func (c *Config) Parse() {
 			c.env[k] = v
 		}
 	}
+
+	for k, v := range c.mapEnv {
+		for mk, mv := range v {
+			mv.parsed = mv.dtype.parse(k+"_"+mk, mv.value)
+			c.mapEnv[k][mk] = mv
+		}
+	}
+
 	if failed {
 		for k, v := range c.env {
 			if (v.parsed.err == nil) && v.unset {
@@ -199,6 +234,17 @@ func (c *Config) Status() (ok bool) {
 				}
 			}
 		}
+		for _, v := range c.mapEnv {
+			for _, mv := range v {
+				err := mv.parsed.err
+				if err != nil {
+					ok = false
+					if !mv.empty {
+						fmt.Fprintln(os.Stderr, err)
+					}
+				}
+			}
+		}
 		if !ok {
 			fmt.Fprintln(os.Stderr, "")
 			for _, v := range c.env {
@@ -212,6 +258,27 @@ func (c *Config) Status() (ok bool) {
 	return
 }
 
+func cleanKey(str string) string {
+	fn := func(r rune) rune {
+		if (r >= '0' && r <= '9') || (r >= 'A' && r <= 'Z') || r == '_' {
+			return r
+		}
+		return -1
+	}
+
+	str = strings.Map(fn, strings.ToUpper(str))
+
+	oldlen := len(str) + 1
+	newlen := len(str)
+	for newlen < oldlen {
+		oldlen = newlen
+		str = strings.ReplaceAll(str, "__", "_")
+		newlen = len(str)
+	}
+
+	return str
+}
+
 func (c *Config) getRaw(key string, dtype DataType) (val cValue) {
 	val.dtype = TypeNone
 	if c.parsed {
@@ -224,6 +291,27 @@ func (c *Config) getRaw(key string, dtype DataType) (val cValue) {
 	return
 }
 
+func (c *Config) getRawMap(key string, dtype DataType) (empty map[string]cValue) {
+	empty = make(map[string]cValue)
+	retval := make(map[string]cValue)
+	if c.parsed {
+		key = cleanKey(key)
+		entries, ok := c.mapEnv[key]
+
+		if ok {
+			for k, v := range entries {
+				if v.dtype == dtype {
+					retval[k] = v.parsed
+				} else {
+					return
+				}
+			}
+			return retval
+		}
+	}
+	return
+}
+
 // GetInt returns the value of an environment variable.
 // If the variable is not defined as envconf.TypeInt the function will return 0.
 func (c *Config) GetInt(key string) int64 {
@@ -270,6 +358,38 @@ func (c *Config) GetBool(key string) bool {
 	return val.boolval
 }
 
+func (c *Config) GetMapInt(key string) (retval map[string]int64) {
+	retval = make(map[string]int64)
+	for k, v := range c.getRawMap(key, TypeInt) {
+		retval[k] = v.intval
+	}
+	return
+}
+
+func (c *Config) GetMapDuration(key string) (retval map[string]time.Duration) {
+	retval = make(map[string]time.Duration)
+	for k, v := range c.getRawMap(key, TypeDuration) {
+		retval[k] = v.durval
+	}
+	return
+}
+
+func (c *Config) GetMapString(key string) (retval map[string]string) {
+	retval = make(map[string]string)
+	for k, v := range c.getRawMap(key, TypeString) {
+		retval[k] = v.strval
+	}
+	return
+}
+
+func (c *Config) GetMapBool(key string) (retval map[string]bool) {
+	retval = make(map[string]bool)
+	for k, v := range c.getRawMap(key, TypeBool) {
+		retval[k] = v.boolval
+	}
+	return
+}
+
 func getFirstRune(str string) rune {
 	for _, v := range str {
 		return v