diff --git a/caldav/caldav.go b/caldav/caldav.go
index 3840c7d..62cc94d 100644
--- a/caldav/caldav.go
+++ b/caldav/caldav.go
@@ -27,19 +27,30 @@ type CalendarCompRequest struct {
 }
 
 type CompFilter struct {
-	Name       string
-	Start, End time.Time
-	Props      []PropFilter
-	Comps      []CompFilter
+	Name         string
+	IsNotDefined bool
+	Start, End   time.Time
+	Props        []PropFilter
+	Comps        []CompFilter
+}
+
+type ParamFilter struct {
+	Name         string
+	IsNotDefined bool
+	TextMatch    *TextMatch
 }
 
 type PropFilter struct {
-	Name      string
-	TextMatch *TextMatch
+	Name         string
+	IsNotDefined bool
+	Start, End   time.Time
+	TextMatch    *TextMatch
+	ParamFilter  []ParamFilter
 }
 
 type TextMatch struct {
-	Text string
+	Text            string
+	NegateCondition bool
 }
 
 type CalendarQuery struct {
diff --git a/caldav/elements.go b/caldav/elements.go
index e1f8c32..7b00fd5 100644
--- a/caldav/elements.go
+++ b/caldav/elements.go
@@ -21,7 +21,8 @@ var (
 	calendarQueryName    = xml.Name{namespace, "calendar-query"}
 	calendarMultigetName = xml.Name{namespace, "calendar-multiget"}
 
-	calendarName = xml.Name{namespace, "calendar"}
+	calendarName     = xml.Name{namespace, "calendar"}
+	calendarDataName = xml.Name{namespace, "calendar-data"}
 )
 
 // https://tools.ietf.org/html/rfc4791#section-6.2.1
@@ -98,19 +99,49 @@ type compFilter struct {
 
 // https://tools.ietf.org/html/rfc4791#section-9.7.2
 type propFilter struct {
-	XMLName      xml.Name   `xml:"urn:ietf:params:xml:ns:caldav prop-filter"`
+	XMLName      xml.Name      `xml:"urn:ietf:params:xml:ns:caldav prop-filter"`
+	Name         string        `xml:"name,attr"`
+	IsNotDefined *struct{}     `xml:"is-not-defined,omitempty"`
+	TimeRange    *timeRange    `xml:"time-range,omitempty"`
+	TextMatch    *textMatch    `xml:"text-match,omitempty"`
+	ParamFilter  []paramFilter `xml:"param-filter,omitempty"`
+}
+
+// https://tools.ietf.org/html/rfc4791#section-9.7.3
+type paramFilter struct {
+	XMLName      xml.Name   `xml:"urn:ietf:params:xml:ns:caldav param-filter"`
 	Name         string     `xml:"name,attr"`
 	IsNotDefined *struct{}  `xml:"is-not-defined,omitempty"`
-	TimeRange    *timeRange `xml:"time-range,omitempty"`
 	TextMatch    *textMatch `xml:"text-match,omitempty"`
-	// TODO: param-filter
 }
 
 // https://tools.ietf.org/html/rfc4791#section-9.7.5
 type textMatch struct {
-	XMLName xml.Name `xml:"urn:ietf:params:xml:ns:caldav text-match"`
-	Text    string   `xml:",chardata"`
-	// TODO: collation, negate-condition
+	XMLName         xml.Name        `xml:"urn:ietf:params:xml:ns:caldav text-match"`
+	Text            string          `xml:",chardata"`
+	Collation       string          `xml:"collation,attr,omitempty"`
+	NegateCondition negateCondition `xml:"negate-condition,attr,omitempty"`
+}
+
+type negateCondition bool
+
+func (nc *negateCondition) UnmarshalText(b []byte) error {
+	switch s := string(b); s {
+	case "yes":
+		*nc = true
+	case "no":
+		*nc = false
+	default:
+		return fmt.Errorf("caldav: invalid negate-condition value: %q", s)
+	}
+	return nil
+}
+
+func (nc negateCondition) MarshalText() ([]byte, error) {
+	if nc {
+		return []byte("yes"), nil
+	}
+	return nil, nil
 }
 
 // https://tools.ietf.org/html/rfc4791#section-9.9
diff --git a/caldav/server.go b/caldav/server.go
index b0ea301..c72acde 100644
--- a/caldav/server.go
+++ b/caldav/server.go
@@ -69,17 +69,53 @@ func (h *Handler) handleReport(w http.ResponseWriter, r *http.Request) error {
 	return internal.HTTPErrorf(http.StatusBadRequest, "caldav: expected calendar-query or calendar-multiget element in REPORT request")
 }
 
-func decodePropFilter(el *propFilter) (*PropFilter, error) {
-	pf := &PropFilter{Name: el.Name}
+func decodeParamFilter(el *paramFilter) (*ParamFilter, error) {
+	pf := &ParamFilter{Name: el.Name}
+	if el.IsNotDefined != nil {
+		if el.TextMatch != nil {
+			return nil, fmt.Errorf("caldav: failed to parse param-filter: if is-not-defined is provided, text-match can't be provided")
+		}
+		pf.IsNotDefined = true
+	}
 	if el.TextMatch != nil {
 		pf.TextMatch = &TextMatch{Text: el.TextMatch.Text}
 	}
-	// TODO: IsNotDefined, TimeRange
+	return pf, nil
+}
+
+func decodePropFilter(el *propFilter) (*PropFilter, error) {
+	pf := &PropFilter{Name: el.Name}
+	if el.IsNotDefined != nil {
+		if el.TextMatch != nil || el.TimeRange != nil || len(el.ParamFilter) > 0 {
+			return nil, fmt.Errorf("caldav: failed to parse prop-filter: if is-not-defined is provided, text-match, time-range, or param-filter can't be provided")
+		}
+		pf.IsNotDefined = true
+	}
+	if el.TextMatch != nil {
+		pf.TextMatch = &TextMatch{Text: el.TextMatch.Text}
+	}
+	if el.TimeRange != nil {
+		pf.Start = time.Time(el.TimeRange.Start)
+		pf.End = time.Time(el.TimeRange.End)
+	}
+	for _, paramEl := range el.ParamFilter {
+		paramFi, err := decodeParamFilter(&paramEl)
+		if err != nil {
+			return nil, err
+		}
+		pf.ParamFilter = append(pf.ParamFilter, *paramFi)
+	}
 	return pf, nil
 }
 
 func decodeCompFilter(el *compFilter) (*CompFilter, error) {
 	cf := &CompFilter{Name: el.Name}
+	if el.IsNotDefined != nil {
+		if el.TimeRange != nil || len(el.PropFilters) > 0 || len(el.CompFilters) > 0 {
+			return nil, fmt.Errorf("caldav: failed to parse comp-filter: if is-not-defined is provided, time-range, prop-filter, or comp-filter can't be provided")
+		}
+		cf.IsNotDefined = true
+	}
 	if el.TimeRange != nil {
 		cf.Start = time.Time(el.TimeRange.Start)
 		cf.End = time.Time(el.TimeRange.End)
@@ -98,7 +134,6 @@ func decodeCompFilter(el *compFilter) (*CompFilter, error) {
 		}
 		cf.Comps = append(cf.Comps, *child)
 	}
-	// TODO: IsNotDefined
 	return cf, nil
 }