diff --git a/.changes/unreleased/Feature-20231115-143536.yaml b/.changes/unreleased/Feature-20231115-143536.yaml
new file mode 100644
index 00000000..4785d358
--- /dev/null
+++ b/.changes/unreleased/Feature-20231115-143536.yaml
@@ -0,0 +1,3 @@
+kind: Feature
+body: Add support for Property Definitions
+time: 2023-12-07T15:22:26.29648-05:00
diff --git a/property.go b/property.go
new file mode 100644
index 00000000..a0de1c9f
--- /dev/null
+++ b/property.go
@@ -0,0 +1,89 @@
+package opslevel
+
+import "fmt"
+
+type PropertyDefinitionInput struct {
+	Name   string     `json:"name"`
+	Schema JSONString `json:"schema"`
+}
+
+type PropertyDefinition struct {
+	Aliases []string `graphql:"aliases" json:"aliases"`
+	Id      ID       `graphql:"id" json:"id"`
+	Name    string   `graphql:"name" json:"name"`
+	Schema  JSON     `json:"schema" scalar:"true"` // Do not add graphql struct tag here
+}
+
+type PropertyDefinitionConnection struct {
+	Nodes      []PropertyDefinition
+	PageInfo   PageInfo
+	TotalCount int `graphql:"-"`
+}
+
+func (client *Client) CreatePropertyDefinition(input PropertyDefinitionInput) (*PropertyDefinition, error) {
+	var m struct {
+		Payload struct {
+			Definition PropertyDefinition `graphql:"definition"`
+			Errors     []OpsLevelErrors   `graphql:"errors"`
+		} `graphql:"propertyDefinitionCreate(input: $input)"`
+	}
+	v := PayloadVariables{
+		"input": input,
+	}
+	err := client.Mutate(&m, v, WithName("PropertyDefinitionCreate"))
+	return &m.Payload.Definition, HandleErrors(err, m.Payload.Errors)
+}
+
+func (client *Client) GetPropertyDefinition(input string) (*PropertyDefinition, error) {
+	var q struct {
+		Account struct {
+			Definition PropertyDefinition `graphql:"propertyDefinition(input: $input)"`
+		}
+	}
+	v := PayloadVariables{
+		"input": *NewIdentifier(input),
+	}
+	err := client.Query(&q, v, WithName("PropertyDefinitionGet"))
+	if q.Account.Definition.Id == "" {
+		err = fmt.Errorf("PropertyDefinition with ID or Alias matching '%s' not found", input)
+	}
+	return &q.Account.Definition, HandleErrors(err, nil)
+}
+
+func (client *Client) ListPropertyDefinitions(variables *PayloadVariables) (PropertyDefinitionConnection, error) {
+	var q struct {
+		Account struct {
+			Definitions PropertyDefinitionConnection `graphql:"propertyDefinitions(after: $after, first: $first)"`
+		}
+	}
+	if variables == nil {
+		variables = client.InitialPageVariablesPointer()
+	}
+	if err := client.Query(&q, *variables, WithName("PropertyDefinitionList")); err != nil {
+		return PropertyDefinitionConnection{}, err
+	}
+	for q.Account.Definitions.PageInfo.HasNextPage {
+		(*variables)["after"] = q.Account.Definitions.PageInfo.End
+		resp, err := client.ListPropertyDefinitions(variables)
+		if err != nil {
+			return PropertyDefinitionConnection{}, err
+		}
+		q.Account.Definitions.Nodes = append(q.Account.Definitions.Nodes, resp.Nodes...)
+		q.Account.Definitions.PageInfo = resp.PageInfo
+		q.Account.Definitions.TotalCount += len(q.Account.Definitions.Nodes)
+	}
+	return q.Account.Definitions, nil
+}
+
+func (client *Client) DeletePropertyDefinition(input string) error {
+	var m struct {
+		Payload struct {
+			Errors []OpsLevelErrors `graphql:"errors"`
+		} `graphql:"propertyDefinitionDelete(resource: $input)"`
+	}
+	v := PayloadVariables{
+		"input": *NewIdentifier(input),
+	}
+	err := client.Mutate(&m, v, WithName("PropertyDefinitionDelete"))
+	return HandleErrors(err, m.Payload.Errors)
+}
diff --git a/property_test.go b/property_test.go
new file mode 100644
index 00000000..63ba2416
--- /dev/null
+++ b/property_test.go
@@ -0,0 +1,135 @@
+package opslevel_test
+
+import (
+	"fmt"
+	"testing"
+
+	ol "github.com/opslevel/opslevel-go/v2023"
+	"github.com/rocktavious/autopilot/v2023"
+)
+
+const schemaString = `{"$ref":"#/$defs/MyProp","$defs":{"MyProp":{"properties":{"name":{"type":"string","title":"the name","description":"The name of a friend","default":"alex","examples":["joe","lucy"]}},"additionalProperties":false,"type":"object","required":["name"]}}}`
+
+func TestCreatePropertyDefinition(t *testing.T) {
+	// Arrange
+	schema := ol.NewJSON(schemaString)
+	expectedPropertyDefinition := autopilot.Register[ol.PropertyDefinition]("expected_property_definition", ol.PropertyDefinition{
+		Aliases: []string{"my_prop"},
+		Id:      "XXX",
+		Name:    "my-prop",
+		Schema:  schema,
+	})
+	propertyDefinitionInput := autopilot.Register[ol.PropertyDefinitionInput]("property_definition_input", ol.PropertyDefinitionInput{
+		Name:   "my-prop",
+		Schema: ol.JSONString(schemaString),
+	})
+	testRequest := NewTestRequest(
+		`"mutation PropertyDefinitionCreate($input:PropertyDefinitionInput!){propertyDefinitionCreate(input: $input){definition{aliases,id,name,schema},errors{message,path}}}"`,
+		`{"input": {{ template "property_definition_input" }} }`,
+		fmt.Sprintf(`{"data":{"propertyDefinitionCreate":{"definition": {"aliases":["my_prop"],"id":"XXX","name":"my-prop","schema": %s}, "errors":[] }}}`, schema.ToJSON()),
+	)
+	client := BestTestClient(t, "properties/definition_create", testRequest)
+
+	// Act
+	actualPropertyDefinition, err := client.CreatePropertyDefinition(propertyDefinitionInput)
+
+	// Assert
+	autopilot.Ok(t, err)
+	autopilot.Equals(t, expectedPropertyDefinition, *actualPropertyDefinition)
+	autopilot.Equals(t, ol.JSON(propertyDefinitionInput.Schema.Map()), actualPropertyDefinition.Schema)
+}
+
+func TestDeletePropertyDefinition(t *testing.T) {
+	// Arrange
+	testRequest := NewTestRequest(
+		`"mutation PropertyDefinitionDelete($input:IdentifierInput!){propertyDefinitionDelete(resource: $input){errors{message,path}}}"`,
+		`{"input":{"alias":"my_prop"}}`,
+		`{"data":{"propertyDefinitionDelete":{"errors":[]}}}`,
+	)
+	client := BestTestClient(t, "properties/definition_delete", testRequest)
+
+	// Act
+	err := client.DeletePropertyDefinition("my_prop")
+
+	// Assert
+	autopilot.Ok(t, err)
+}
+
+func TestGetPropertyDefinition(t *testing.T) {
+	// Arrange
+	schema := ol.NewJSON(schemaString)
+	expectedPropertyDefinition := autopilot.Register[ol.PropertyDefinition]("expected_property_definition",
+		ol.PropertyDefinition{
+			Aliases: []string{"my_prop"},
+			Id:      "XXX",
+			Name:    "my-prop",
+			Schema:  schema,
+		})
+	testRequest := NewTestRequest(
+		`"query PropertyDefinitionGet($input:IdentifierInput!){account{propertyDefinition(input: $input){aliases,id,name,schema}}}"`,
+		`{"input":{"alias":"my_prop"}}`,
+		fmt.Sprintf(`{"data":{"account":{"propertyDefinition": {"aliases":["my_prop"],"id":"XXX","name":"my-prop","schema": %s }}}}`, schema.ToJSON()),
+	)
+	client := BestTestClient(t, "properties/definition_get", testRequest)
+
+	// Act
+	property, err := client.GetPropertyDefinition("my_prop")
+
+	// Assert
+	autopilot.Ok(t, err)
+	autopilot.Equals(t, "XXX", string(property.Id))
+	autopilot.Equals(t, expectedPropertyDefinition, *property)
+	autopilot.Equals(t, "my-prop", property.Name)
+	autopilot.Equals(t, schema, property.Schema)
+}
+
+func TestListPropertyDefinitions(t *testing.T) {
+	// Arrange
+	schema := ol.NewJSON(schemaString)
+	expectedPropDefsPageOne := autopilot.Register[[]ol.PropertyDefinition]("property_definitions", []ol.PropertyDefinition{
+		{
+			Aliases: []string{"prop1"},
+			Id:      "XXX",
+			Name:    "prop1",
+			Schema:  ol.NewJSON(schemaString),
+		},
+		{
+			Aliases: []string{"prop2"},
+			Id:      "XXX",
+			Name:    "prop2",
+			Schema:  ol.NewJSON(schemaString),
+		},
+	})
+	expectedPropDefPageTwo := autopilot.Register[ol.PropertyDefinition]("property_definition_3", ol.PropertyDefinition{
+		Aliases: []string{"prop3"},
+		Id:      "XXX",
+		Name:    "prop3",
+		Schema:  ol.NewJSON(schemaString),
+	})
+	testRequestOne := NewTestRequest(
+		`"query PropertyDefinitionList($after:String!$first:Int!){account{propertyDefinitions(after: $after, first: $first){nodes{aliases,id,name,schema},{{ template "pagination_request" }}}}}"`,
+		`{{ template "pagination_initial_query_variables" }}`,
+		fmt.Sprintf(`{"data":{"account":{"propertyDefinitions":{"nodes":[{"aliases":["prop1"],"id":"XXX","name":"prop1","schema": %s},{"aliases":["prop2"],"id":"XXX","name":"prop2","schema": %s}],{{ template "pagination_initial_pageInfo_response" }}}}}}`, schema.ToJSON(), schema.ToJSON()),
+	)
+	testRequestTwo := NewTestRequest(
+		`"query PropertyDefinitionList($after:String!$first:Int!){account{propertyDefinitions(after: $after, first: $first){nodes{aliases,id,name,schema},{{ template "pagination_request" }}}}}"`,
+		`{{ template "pagination_second_query_variables" }}`,
+		fmt.Sprintf(`{"data":{"account":{"propertyDefinitions":{"nodes":[{"aliases":["prop3"],"id":"XXX","name":"prop3","schema": %s}],{{ template "pagination_second_pageInfo_response" }}}}}}`, schema.ToJSON()),
+	)
+	requests := []TestRequest{testRequestOne, testRequestTwo}
+	client := BestTestClient(t, "properties/definition_list", requests...)
+
+	// Act
+	properties, err := client.ListPropertyDefinitions(nil)
+	result := properties.Nodes
+
+	// Assert
+	autopilot.Ok(t, err)
+	autopilot.Equals(t, 3, len(result))
+	autopilot.Equals(t, expectedPropDefsPageOne[0], result[0])
+	autopilot.Equals(t, expectedPropDefsPageOne[1], result[1])
+	autopilot.Equals(t, expectedPropDefPageTwo, result[2])
+	autopilot.Equals(t, expectedPropDefsPageOne[0].Schema, result[0].Schema)
+	autopilot.Equals(t, expectedPropDefsPageOne[1].Schema, result[1].Schema)
+	autopilot.Equals(t, expectedPropDefPageTwo.Schema, result[2].Schema)
+}